restyle activity card as a holder container; background-toggle collapse (T-266)

Extracts a shared ClideHolderCard primitive (consumed next by T-264) that
renders a folded run as one framed container wrapping its sub-cards:

- The whole holder background is the collapse toggle — a gesture target
  behind the children that only fires for hits the children don't consume.
  Each sub-card opaquely absorbs its own bounds, so a card tap (and its
  copy button) interacts with the card, never the holder; selection drags
  pass through. This ends the scroll race: while a run tail-follows, a
  click on whatever background is in view collapses it, no top header to
  reach.
- A focusable caret keeps the control keyboard/AT reachable (D-78); the
  collapsed ticker + step count are preserved.
- _ActivityCard becomes a thin stateless adopter of the primitive.

Tests: ticker/expand, background-toggle, child-tap-not-hijacked, copy
still works, keyboard Activate path; golden for collapsed + expanded.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

.pql/changelog/ticket_history/2026-06.sql

@@ -815,3 +815,5 @@ Once this lands, loose UI/UX work + bugs can move from the T-276 tracker-epic to
 Relevant: lib/builtin/tickets/, lib/src/pql/ (pql wrapper), and pql''s ''ticket label'' / ''ticket list'' label fields.', NULL, '2026-06-08 08:34:24', '2026-06-08 08:34:24', '2026-06-08 08:34:24', NULL, '499355d06a5e7618a1c32e63a6cd1bcd', 1) ON CONFLICT(hash) DO NOTHING;
 INSERT INTO ticket_history (ticket_id, field, old_value, new_value, changed_by, changed_at, created_at, updated_at, deleted_at, hash, canonical_version) VALUES ('T-277', 'parent_id', NULL, 'T-276', NULL, '2026-06-08 08:34:47', '2026-06-08 08:34:47', '2026-06-08 08:34:47', NULL, '67d78cbf1e92166d60e45b3f51ed440e', 1) ON CONFLICT(hash) DO NOTHING;
 INSERT INTO ticket_history (ticket_id, field, old_value, new_value, changed_by, changed_at, created_at, updated_at, deleted_at, hash, canonical_version) VALUES ('T-263', 'status', 'in_progress', 'done', NULL, '2026-06-08 08:45:23', '2026-06-08 08:45:23', '2026-06-08 08:45:23', NULL, '7e18bb85a36603663881ebd55d77d308', 1) ON CONFLICT(hash) DO NOTHING;
+INSERT INTO ticket_history (ticket_id, field, old_value, new_value, changed_by, changed_at, created_at, updated_at, deleted_at, hash, canonical_version) VALUES ('T-266', 'status', 'backlog', 'in_progress', NULL, '2026-06-08 08:47:43', '2026-06-08 08:47:43', '2026-06-08 08:47:43', NULL, '0eebe9e270a6a7a4b9cccfb9ffbe5dc4', 1) ON CONFLICT(hash) DO NOTHING;
+INSERT INTO ticket_history (ticket_id, field, old_value, new_value, changed_by, changed_at, created_at, updated_at, deleted_at, hash, canonical_version) VALUES ('T-266', 'status', 'in_progress', 'done', NULL, '2026-06-08 09:04:12', '2026-06-08 09:04:12', '2026-06-08 09:04:12', NULL, 'fecc7bc78e18d5dd3c613d6583371fc3', 1) ON CONFLICT(hash) DO NOTHING;

.pql/changelog/tickets/2026-06.sql

@@ -1873,3 +1873,63 @@ Refs: D-78 (interaction zone / display-only conversation widgets; injected/conte
 IMPLEMENTATION NOTE (E — Agent-card layered ordering, from streamlining analysis):
 
 With this ticket (fold prompt) and T-262 (merge success result) both landing, the Agent/Task card ends up owning multiple segments: the tool INPUT, the folded PROMPT, and — via T-262 — the sub-agents final returned RESULT (the Task ToolResultMessage). Define a deliberate layered order when expanded (e.g. call/input → prompt → returned result) with clear sub-labels/dividers so the Agent card stays readable and does not become a kitchen sink. Coordinate with T-262 (result merge) and T-264 (nesting the whole run): the nested run region vs the returned-result segment must not duplicate the sub-agent output.', 'done', 'medium', NULL, NULL, 'D-78', '2026-06-07 08:34:02', '2026-06-08 08:45:23', NULL, '561ac6a3308d08c0da27bcb23eb21cc0', 1) ON CONFLICT(id) DO UPDATE SET type=excluded.type, parent_id=excluded.parent_id, title=excluded.title, description=excluded.description, status=excluded.status, priority=excluded.priority, assigned_to=excluded.assigned_to, team=excluded.team, decision_ref=excluded.decision_ref, updated_at=excluded.updated_at, deleted_at=excluded.deleted_at, hash=excluded.hash, canonical_version=excluded.canonical_version WHERE excluded.updated_at > tickets.updated_at OR (excluded.updated_at = tickets.updated_at AND excluded.hash > tickets.hash);
+INSERT INTO tickets (id, type, parent_id, title, description, status, priority, assigned_to, team, decision_ref, created_at, updated_at, deleted_at, hash, canonical_version) VALUES ('T-266', 'story', 'T-267', 'Restyle activity/holder card as a container of sub-cards (fix collapse-control scroll race)', 'Restyle the activity card (and, via a shared primitive, the nested sub-agent run from T-264) so a folded run reads as ONE container that holds its sub-cards, with a reachable collapse/expand affordance that survives live writes.
+
+DESIGN RESOLVED (with user) — supersedes the earlier design-pending note.
+
+1. HOLDER = a shared container primitive. Extract one container widget (e.g. a ClideHolderCard / conversation-level container) that renders a titled/attributed frame WRAPPING its child sub-cards. Both the activity card (_ActivityCard, lib/builtin/claude/src/conversation_view.dart ~L427) and the nested sub-agent run (T-264) consume it, so the container model is settled once. NOTE: this makes T-266 a DEPENDENCY of T-264 (the shared primitive must exist before the agent-run nesting can consume it) — update epic T-267 sequencing: T-266''s primitive lands before/with T-264, no longer strictly last.
+
+2. Toggle = the HOLDER BACKGROUND, not the children. Clicking the container''s own background/chrome (its padding, the gaps between sub-cards, its gutter — any region NOT covered by a child) toggles collapse/expand. Crucially:
+- Taps on a child sub-card lying on top of the background MUST NOT toggle the holder. Child cards opaquely consume their own hit region across their FULL bounds (including their body), so a click on a sub-card interacts with that card, never the holder.
+- The copy button (and any child control / ClideTappable) keeps its own interaction — never swallowed by the holder toggle.
+- Implementation: a background gesture target behind the children that only fires for hits the children do not consume (HitTestBehavior; children opaque over their bounds). No whole-card overlay that would intercept child taps.
+
+3. Autoscroll stays ALWAYS-FOLLOW. Keep the current tail-follow (conversation_view._onChanged ~L119 jumps to maxScrollExtent on every change). Reachability of the collapse control no longer depends on getting to a top header: because the toggle is the ever-present holder BACKGROUND, a click on whatever background area is currently in view (near the latest content while following) collapses the holder — ending the race. Once collapsed the card shrinks to its ticker, so the scroll-yank stops.
+
+4. Keep the collapsed ticker. Collapsed (default) still shows the one-line live ticker (latest step) + step count, as today. Expanded shows the contained sub-cards.
+
+5. Accessibility (obligation): a background tap is not keyboard/AT reachable on its own, so keep an EXPLICIT focusable, Enter/Space-activatable collapse control (e.g. the ticker row remains a Semantics button / a focusable caret) in addition to the background-click affordance. Announce expanded/collapsed + step count (as _ActivityCard does today).
+
+Touch points:
+- New shared container primitive (extracted from _ActivityCard).
+- conversation_view.dart: _ActivityCard adopts the primitive; background-toggle wiring; ensure child ConversationCards opaquely consume their bounds so they do not bubble taps to the holder.
+- T-264 consumes the same primitive for the nested agent run.
+
+Edge cases:
+- A holder whose child is itself collapsible (a tool card): tapping the child''s caret/body toggles the CHILD, never the holder.
+- Text selection inside a child (ClideSelectionArea wraps the list): selection drags on child bodies must not be hijacked by the holder toggle — another reason the holder responds only to its own background, and only to taps (not drags).
+- Empty / single-item holder.
+
+Tests: holder background tap toggles; tap on a child sub-card does NOT toggle the holder; copy button still copies (not swallowed); keyboard/AT path toggles via the explicit control; collapsed ticker + step count preserved. Add a golden for the holder container (collapsed + expanded).
+
+Refs: D-78. Provides the shared container consumed by T-264. Related: T-230 (activity card), T-262 / T-263 / T-265. Parent: T-267.', 'in_progress', 'medium', NULL, NULL, 'D-78', '2026-06-07 08:41:13', '2026-06-08 08:47:43', NULL, 'c983e4459c327d71c9783c06286f4b49', 1) ON CONFLICT(id) DO UPDATE SET type=excluded.type, parent_id=excluded.parent_id, title=excluded.title, description=excluded.description, status=excluded.status, priority=excluded.priority, assigned_to=excluded.assigned_to, team=excluded.team, decision_ref=excluded.decision_ref, updated_at=excluded.updated_at, deleted_at=excluded.deleted_at, hash=excluded.hash, canonical_version=excluded.canonical_version WHERE excluded.updated_at > tickets.updated_at OR (excluded.updated_at = tickets.updated_at AND excluded.hash > tickets.hash);
+INSERT INTO tickets (id, type, parent_id, title, description, status, priority, assigned_to, team, decision_ref, created_at, updated_at, deleted_at, hash, canonical_version) VALUES ('T-266', 'story', 'T-267', 'Restyle activity/holder card as a container of sub-cards (fix collapse-control scroll race)', 'Restyle the activity card (and, via a shared primitive, the nested sub-agent run from T-264) so a folded run reads as ONE container that holds its sub-cards, with a reachable collapse/expand affordance that survives live writes.
+
+DESIGN RESOLVED (with user) — supersedes the earlier design-pending note.
+
+1. HOLDER = a shared container primitive. Extract one container widget (e.g. a ClideHolderCard / conversation-level container) that renders a titled/attributed frame WRAPPING its child sub-cards. Both the activity card (_ActivityCard, lib/builtin/claude/src/conversation_view.dart ~L427) and the nested sub-agent run (T-264) consume it, so the container model is settled once. NOTE: this makes T-266 a DEPENDENCY of T-264 (the shared primitive must exist before the agent-run nesting can consume it) — update epic T-267 sequencing: T-266''s primitive lands before/with T-264, no longer strictly last.
+
+2. Toggle = the HOLDER BACKGROUND, not the children. Clicking the container''s own background/chrome (its padding, the gaps between sub-cards, its gutter — any region NOT covered by a child) toggles collapse/expand. Crucially:
+- Taps on a child sub-card lying on top of the background MUST NOT toggle the holder. Child cards opaquely consume their own hit region across their FULL bounds (including their body), so a click on a sub-card interacts with that card, never the holder.
+- The copy button (and any child control / ClideTappable) keeps its own interaction — never swallowed by the holder toggle.
+- Implementation: a background gesture target behind the children that only fires for hits the children do not consume (HitTestBehavior; children opaque over their bounds). No whole-card overlay that would intercept child taps.
+
+3. Autoscroll stays ALWAYS-FOLLOW. Keep the current tail-follow (conversation_view._onChanged ~L119 jumps to maxScrollExtent on every change). Reachability of the collapse control no longer depends on getting to a top header: because the toggle is the ever-present holder BACKGROUND, a click on whatever background area is currently in view (near the latest content while following) collapses the holder — ending the race. Once collapsed the card shrinks to its ticker, so the scroll-yank stops.
+
+4. Keep the collapsed ticker. Collapsed (default) still shows the one-line live ticker (latest step) + step count, as today. Expanded shows the contained sub-cards.
+
+5. Accessibility (obligation): a background tap is not keyboard/AT reachable on its own, so keep an EXPLICIT focusable, Enter/Space-activatable collapse control (e.g. the ticker row remains a Semantics button / a focusable caret) in addition to the background-click affordance. Announce expanded/collapsed + step count (as _ActivityCard does today).
+
+Touch points:
+- New shared container primitive (extracted from _ActivityCard).
+- conversation_view.dart: _ActivityCard adopts the primitive; background-toggle wiring; ensure child ConversationCards opaquely consume their bounds so they do not bubble taps to the holder.
+- T-264 consumes the same primitive for the nested agent run.
+
+Edge cases:
+- A holder whose child is itself collapsible (a tool card): tapping the child''s caret/body toggles the CHILD, never the holder.
+- Text selection inside a child (ClideSelectionArea wraps the list): selection drags on child bodies must not be hijacked by the holder toggle — another reason the holder responds only to its own background, and only to taps (not drags).
+- Empty / single-item holder.
+
+Tests: holder background tap toggles; tap on a child sub-card does NOT toggle the holder; copy button still copies (not swallowed); keyboard/AT path toggles via the explicit control; collapsed ticker + step count preserved. Add a golden for the holder container (collapsed + expanded).
+
+Refs: D-78. Provides the shared container consumed by T-264. Related: T-230 (activity card), T-262 / T-263 / T-265. Parent: T-267.', 'done', 'medium', NULL, NULL, 'D-78', '2026-06-07 08:41:13', '2026-06-08 09:04:12', NULL, '9da8b26d36d66bf1d26125519ec45872', 1) ON CONFLICT(id) DO UPDATE SET type=excluded.type, parent_id=excluded.parent_id, title=excluded.title, description=excluded.description, status=excluded.status, priority=excluded.priority, assigned_to=excluded.assigned_to, team=excluded.team, decision_ref=excluded.decision_ref, updated_at=excluded.updated_at, deleted_at=excluded.deleted_at, hash=excluded.hash, canonical_version=excluded.canonical_version WHERE excluded.updated_at > tickets.updated_at OR (excluded.updated_at = tickets.updated_at AND excluded.hash > tickets.hash);

CHANGELOG.md

@@ -144,6 +144,11 @@ heading, and (b) bumping `pubspec.yaml` `version:` in the same commit.
 
 ### Changed
 
+- The folded **activity card** now reads as one **container that wraps its
+  sub-cards**, and you can collapse it by clicking anywhere on the holder's own
+  background — not just a top header that scrolls out of reach while a run
+  streams. Taps on a sub-card (and its copy button) still interact with that
+  card. A focusable caret keeps the control keyboard/AT reachable. (T-266)
 - A **sub-agent prompt** is no longer mislabelled as your input: a sidechain
   prompt now reads as a muted **`agent prompt`** (never the blue `you`) and folds
   into its **Agent/Task card**, collapsed by default. The prompt attaches to the

lib/builtin/claude/src/conversation_view.dart

@@ -15,6 +15,7 @@ import 'dart:io';
 import 'package:clide/builtin/claude/src/activity_cluster.dart';
 import 'package:clide/builtin/claude/src/conversation_card.dart';
 import 'package:clide/builtin/claude/src/conversation_controller.dart';
+import 'package:clide/builtin/claude/src/holder_card.dart';
 import 'package:clide/builtin/claude/src/prompt_card.dart';
 import 'package:clide/builtin/claude/src/transcript_reader.dart';
 import 'package:clide/kernel/src/facade.dart';
@@ -541,12 +542,12 @@ class _ConversationTurn extends StatelessWidget {
 }
 
 /// A folded run of meta items rendered as one collapsible activity card
-/// (T-230). Collapsed (default): a one-line live ticker of the latest step +
+/// (T-230), now through the shared [ClideHolderCard] container (T-266).
-/// a step count — re-grouped on every rebuild, so the ticker updates in place
+/// Collapsed (default): a one-line live ticker of the latest step + a step
-/// as the run grows. Expanded: every folded step in order. Keyboard + screen
+/// count — re-grouped on every rebuild, so the ticker updates in place as the
-/// reader accessible: [ClideTappable] activates on Enter/Space, and the
+/// run grows. Expanded: every folded step, wrapped in the holder frame whose
-/// Semantics announces the step count + expanded/collapsed state.
+/// background toggles collapse. Stateless — the holder owns the expand state.
-class _ActivityCard extends StatefulWidget {
+class _ActivityCard extends StatelessWidget {
   const _ActivityCard({
     required this.items,
     required this.tokens,
@@ -563,81 +564,23 @@ class _ActivityCard extends StatefulWidget {
   final Map<String, ToolResultMessage> resultByToolUseId;
   final Map<String, List<UserMessage>> promptsByToolUseId;
 
-  @override
-  State<_ActivityCard> createState() => _ActivityCardState();
-}
-
-class _ActivityCardState extends State<_ActivityCard> {
-  bool _expanded = false;
-
   @override
   Widget build(BuildContext context) {
-    final tokens = widget.tokens;
+    final count = items.length;
-    final count = widget.items.length;
+    return ClideHolderCard(
-    final stepLabel = count == 1 ? '1 step' : '$count steps';
+      collapsedSummary: _summarizeActivity(items.last),
-
+      stepLabel: count == 1 ? '1 step' : '$count steps',
-    final header = ClideTappable(
+      children: [
-      onTap: () => setState(() => _expanded = !_expanded),
+        for (final item in items)
-      builder: (context, hovered, focused) => Container(
+          _ConversationTurn(
-        padding: const EdgeInsets.symmetric(horizontal: 10, vertical: 6),
+            item: item,
-        decoration: BoxDecoration(
+            tokens: tokens,
-          color: (hovered || focused) ? tokens.listItemHoverBackground : tokens.listItemBackground,
+            toolUseOutcomes: toolUseOutcomes,
-          border: Border.all(color: tokens.panelBorder),
+            toolUseById: toolUseById,
-          borderRadius: BorderRadius.circular(4),
+            resultByToolUseId: resultByToolUseId,
-        ),
+            promptsByToolUseId: promptsByToolUseId,
-        child: Row(
+          ),
-          children: [
+      ],
-            ClideIcon(_expanded ? const ChevronDownIcon() : const ChevronRightIcon(), size: 12, color: tokens.globalTextMuted),
-            const SizedBox(width: 8),
-            Expanded(
-              child: ClideText(
-                _expanded ? 'Activity' : _summarizeActivity(widget.items.last),
-                fontSize: clideFontCaption,
-                fontFamily: clideMonoFamily,
-                color: tokens.globalTextMuted,
-                maxLines: 1,
-                overflow: TextOverflow.ellipsis,
-              ),
-            ),
-            const SizedBox(width: 8),
-            ClideText(stepLabel, fontSize: clideFontCaption, color: tokens.globalTextMuted),
-          ],
-        ),
-      ),
-    );
-
-    return Semantics(
-      button: true,
-      expanded: _expanded,
-      label: 'Activity, $stepLabel, ${_expanded ? 'expanded' : 'collapsed'}',
-      excludeSemantics: true,
-      child: Padding(
-        padding: const EdgeInsets.symmetric(vertical: 3),
-        child: Column(
-          crossAxisAlignment: CrossAxisAlignment.stretch,
-          children: [
-            header,
-            if (_expanded)
-              Padding(
-                padding: const EdgeInsets.only(left: 12, top: 2),
-                child: Column(
-                  crossAxisAlignment: CrossAxisAlignment.stretch,
-                  children: [
-                    for (final item in widget.items)
-                      _ConversationTurn(
-                        item: item,
-                        tokens: tokens,
-                        toolUseOutcomes: widget.toolUseOutcomes,
-                        toolUseById: widget.toolUseById,
-                        resultByToolUseId: widget.resultByToolUseId,
-                        promptsByToolUseId: widget.promptsByToolUseId,
-                      ),
-                  ],
-                ),
-              ),
-          ],
-        ),
-      ),
     );
   }
 }

lib/builtin/claude/src/holder_card.dart

@@ -0,0 +1,191 @@
+/// A collapsible container that holds a run of sub-cards as one unit (T-266).
+///
+/// Collapsed (default): a one-line ticker — the latest step summary + a step
+/// count — that toggles to expand. Expanded: a titled, framed container that
+/// WRAPS the sub-cards; clicking the holder's own BACKGROUND (its padding, the
+/// gaps between sub-cards, its gutter — anywhere a child doesn't cover)
+/// collapses it. Taps on a child sub-card interact with that card, never the
+/// holder, because each child opaquely consumes its full bounds.
+///
+/// Why a background toggle (not just a top header): the conversation
+/// tail-follows on every write, so a top-anchored collapse control is
+/// unreachable while a run streams. A click on whatever background is currently
+/// in view collapses the holder, ending that race. An explicit focusable caret
+/// keeps the control keyboard/AT reachable (D-78).
+///
+/// Shared primitive: the activity card (T-230) and the nested sub-agent run
+/// (T-264) both render through this, so the container model is settled once.
+library;
+
+import 'package:clide/kernel/src/theme/controller.dart';
+import 'package:clide/kernel/src/theme/tokens.dart';
+import 'package:clide/widgets/widgets.dart';
+import 'package:flutter/widgets.dart';
+
+class ClideHolderCard extends StatefulWidget {
+  const ClideHolderCard({
+    super.key,
+    required this.collapsedSummary,
+    required this.stepLabel,
+    required this.children,
+    this.title = 'Activity',
+    this.initiallyExpanded = false,
+  });
+
+  /// One-line gist of the latest step, shown in the collapsed ticker.
+  final String collapsedSummary;
+
+  /// Count label, e.g. `3 steps` — shown in both the ticker and the header,
+  /// and announced for AT.
+  final String stepLabel;
+
+  /// The sub-cards, shown wrapped when expanded.
+  final List<Widget> children;
+
+  /// Title shown in the expanded header (default `Activity`).
+  final String title;
+
+  final bool initiallyExpanded;
+
+  @override
+  State<ClideHolderCard> createState() => _ClideHolderCardState();
+}
+
+class _ClideHolderCardState extends State<ClideHolderCard> {
+  late bool _expanded = widget.initiallyExpanded;
+  final FocusNode _controlFocus = FocusNode(debugLabel: 'holder-control');
+
+  @override
+  void dispose() {
+    _controlFocus.dispose();
+    super.dispose();
+  }
+
+  void _toggle() => setState(() => _expanded = !_expanded);
+
+  @override
+  Widget build(BuildContext context) {
+    final tokens = ClideTheme.of(context).surface;
+    return Semantics(
+      button: true,
+      expanded: _expanded,
+      label: '${widget.title}, ${widget.stepLabel}, ${_expanded ? 'expanded' : 'collapsed'}',
+      excludeSemantics: true,
+      child: Padding(
+        padding: const EdgeInsets.symmetric(vertical: 3),
+        child: _expanded ? _expandedFrame(tokens) : _tickerRow(tokens),
+      ),
+    );
+  }
+
+  /// Collapsed: the ticker row IS the toggle, focusable for keyboard/AT.
+  Widget _tickerRow(SurfaceTokens tokens) => ClideTappable(
+        focusNode: _controlFocus,
+        onTap: _toggle,
+        tooltip: 'Expand',
+        builder: (context, hovered, focused) => Container(
+          padding: const EdgeInsets.symmetric(horizontal: 10, vertical: 6),
+          decoration: BoxDecoration(
+            color: (hovered || focused) ? tokens.listItemHoverBackground : tokens.listItemBackground,
+            border: Border.all(color: tokens.panelBorder),
+            borderRadius: BorderRadius.circular(4),
+          ),
+          child: Row(
+            children: [
+              ClideIcon(const ChevronRightIcon(), size: 12, color: tokens.globalTextMuted),
+              const SizedBox(width: 8),
+              Expanded(
+                child: ClideText(
+                  widget.collapsedSummary,
+                  fontSize: clideFontCaption,
+                  fontFamily: clideMonoFamily,
+                  color: tokens.globalTextMuted,
+                  maxLines: 1,
+                  overflow: TextOverflow.ellipsis,
+                ),
+              ),
+              const SizedBox(width: 8),
+              ClideText(widget.stepLabel, fontSize: clideFontCaption, color: tokens.globalTextMuted),
+            ],
+          ),
+        ),
+      );
+
+  /// Expanded: a framed container wrapping the sub-cards. The frame BACKGROUND
+  /// is a gesture target behind the children that only fires for hits the
+  /// children don't consume.
+  Widget _expandedFrame(SurfaceTokens tokens) => DecoratedBox(
+        decoration: BoxDecoration(
+          border: Border.all(color: tokens.panelBorder),
+          borderRadius: BorderRadius.circular(4),
+        ),
+        child: Stack(
+          children: [
+            // Background toggle: behind the children, not a whole-card overlay,
+            // so child taps are never intercepted. Excluded from focus traversal
+            // — the header caret is the single keyboard stop.
+            Positioned.fill(
+              child: ExcludeFocus(
+                child: ClideTappable(
+                  onTap: _toggle,
+                  tooltip: 'Collapse',
+                  builder: (_, __, ___) => const SizedBox.expand(),
+                ),
+              ),
+            ),
+            Column(
+              crossAxisAlignment: CrossAxisAlignment.stretch,
+              children: [
+                _headerRow(tokens),
+                Padding(
+                  padding: const EdgeInsets.fromLTRB(10, 0, 10, 8),
+                  child: Column(
+                    crossAxisAlignment: CrossAxisAlignment.stretch,
+                    children: [
+                      for (final child in widget.children)
+                        // Each child opaquely consumes its full bounds so a body
+                        // tap interacts with the card (or does nothing), never
+                        // the holder background. Deeper controls (caret/copy)
+                        // still win; only taps are absorbed, so selection drags
+                        // pass through to the SelectionArea.
+                        GestureDetector(
+                          behavior: HitTestBehavior.opaque,
+                          onTap: () {},
+                          child: child,
+                        ),
+                    ],
+                  ),
+                ),
+              ],
+            ),
+          ],
+        ),
+      );
+
+  /// The explicit, focusable collapse control. A background tap is not
+  /// keyboard/AT reachable on its own, so this keeps the control on the Tab
+  /// path and Enter/Space-activatable (D-78).
+  Widget _headerRow(SurfaceTokens tokens) => ClideTappable(
+        focusNode: _controlFocus,
+        onTap: _toggle,
+        tooltip: 'Collapse',
+        builder: (context, hovered, focused) => Container(
+          padding: const EdgeInsets.symmetric(horizontal: 10, vertical: 6),
+          decoration: BoxDecoration(
+            color: (hovered || focused) ? tokens.listItemHoverBackground : tokens.listItemBackground,
+            border: Border(bottom: BorderSide(color: tokens.panelBorder)),
+          ),
+          child: Row(
+            children: [
+              ClideIcon(const ChevronDownIcon(), size: 12, color: tokens.globalTextMuted),
+              const SizedBox(width: 8),
+              Expanded(
+                child: ClideText(widget.title, fontSize: clideFontCaption, fontFamily: clideMonoFamily, color: tokens.globalTextMuted),
+              ),
+              const SizedBox(width: 8),
+              ClideText(widget.stepLabel, fontSize: clideFontCaption, color: tokens.globalTextMuted),
+            ],
+          ),
+        ),
+      );
+}

test/builtin/claude/holder_card_test.dart

@@ -0,0 +1,132 @@
+/// Widget tests for the shared [ClideHolderCard] container primitive (T-266):
+/// collapsed ticker, background-as-toggle, child taps not hijacked, the copy
+/// control still works, and the keyboard/AT collapse path.
+library;
+
+import 'package:clide/builtin/claude/src/conversation_card.dart';
+import 'package:clide/builtin/claude/src/holder_card.dart';
+import 'package:flutter/gestures.dart';
+import 'package:flutter/services.dart';
+import 'package:flutter/widgets.dart';
+import 'package:flutter_test/flutter_test.dart';
+
+import '../../helpers/kernel_fixture.dart';
+import '../../helpers/widget_harness.dart';
+
+void main() {
+  late KernelFixture f;
+  setUp(() async {
+    f = await KernelFixture.create();
+    TestWidgetsFlutterBinding.ensureInitialized().defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.platform, (_) async => null);
+  });
+  tearDown(() {
+    TestWidgetsFlutterBinding.ensureInitialized().defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.platform, null);
+    f.dispose();
+  });
+
+  // A tight, positioned tree so the holder's Row/Expanded get a bounded width
+  // and a deterministic on-screen rect for coordinate hit-testing.
+  Future<void> pump(WidgetTester tester, {List<Widget>? children, String summary = 'latest step', bool expanded = false}) async {
+    await tester.pumpWidget(harness(
+      f,
+      Align(
+        alignment: Alignment.topLeft,
+        child: SizedBox(
+          width: 400,
+          child: ClideHolderCard(
+            collapsedSummary: summary,
+            stepLabel: '2 steps',
+            initiallyExpanded: expanded,
+            children: children ??
+                const [
+                  ConversationCard(
+                    variant: ConversationCardVariant.bordered,
+                    accent: Color(0xFFFFFFFF),
+                    label: 'step',
+                    body: Text('child body', textDirection: TextDirection.ltr),
+                  ),
+                ],
+          ),
+        ),
+      ),
+    ));
+    await tester.pump();
+  }
+
+  testWidgets('collapsed shows the ticker summary + step count; tap expands', (tester) async {
+    await pump(tester);
+    expect(find.text('latest step'), findsOneWidget);
+    expect(find.text('2 steps'), findsOneWidget);
+    expect(find.bySemanticsLabel('Activity, 2 steps, collapsed'), findsOneWidget);
+    expect(find.text('child body'), findsNothing); // children hidden while collapsed
+
+    await tester.tap(find.bySemanticsLabel('Activity, 2 steps, collapsed'));
+    await tester.pump();
+    expect(find.bySemanticsLabel('Activity, 2 steps, expanded'), findsOneWidget);
+    expect(find.text('child body'), findsOneWidget);
+  });
+
+  testWidgets('a tap on the holder BACKGROUND (gutter) collapses it', (tester) async {
+    await pump(tester, expanded: true);
+    expect(find.text('child body'), findsOneWidget); // expanded
+
+    // The left gutter (x = left+4) is holder background — children start at
+    // left+10 — and below the header, so this hits the background toggle.
+    final r = tester.getRect(find.byType(ClideHolderCard));
+    await tester.tapAt(Offset(r.left + 4, r.center.dy));
+    await tester.pump();
+    expect(find.text('child body'), findsNothing); // collapsed
+    expect(find.bySemanticsLabel('Activity, 2 steps, collapsed'), findsOneWidget);
+  });
+
+  testWidgets('a tap on a child sub-card does NOT toggle the holder', (tester) async {
+    await pump(tester, expanded: true);
+    expect(find.text('child body'), findsOneWidget);
+
+    // Tapping the child's body must be absorbed by the child, not bubble to the
+    // holder background toggle.
+    await tester.tap(find.text('child body'));
+    await tester.pump();
+    expect(find.text('child body'), findsOneWidget); // still expanded
+    expect(find.bySemanticsLabel('Activity, 2 steps, expanded'), findsOneWidget);
+  });
+
+  testWidgets('a child copy button still copies — not swallowed by the holder', (tester) async {
+    await pump(tester, expanded: true, children: const [
+      ConversationCard(
+        variant: ConversationCardVariant.bordered,
+        accent: Color(0xFFFFFFFF),
+        label: 'step',
+        copyText: 'copied from a held card',
+        body: Text('child body', textDirection: TextDirection.ltr),
+      ),
+    ]);
+
+    // Hover the child to reveal its copy action, then tap it.
+    final g = await tester.createGesture(kind: PointerDeviceKind.mouse);
+    await g.addPointer(location: Offset.zero);
+    addTearDown(() => g.removePointer());
+    await g.moveTo(tester.getCenter(find.byType(ConversationCard)));
+    await tester.pump();
+
+    await tester.tap(find.text('copy'));
+    await tester.runAsync(() => Future<void>.delayed(const Duration(milliseconds: 20)));
+    expect(f.services.clipboard.readAs<String>(), 'copied from a held card');
+    // And the holder stayed expanded (the copy tap wasn't a background toggle).
+    expect(find.bySemanticsLabel('Activity, 2 steps, expanded'), findsOneWidget);
+  });
+
+  testWidgets('the explicit control is keyboard-focusable and toggles on Activate (a11y)', (tester) async {
+    await pump(tester); // collapsed; the ticker row is the control
+    final focusWidget = tester.widget<Focus>(
+      find.ancestor(of: find.text('latest step'), matching: find.byType(Focus)).first,
+    );
+    focusWidget.focusNode!.requestFocus();
+    await tester.pump();
+    expect(focusWidget.focusNode!.hasFocus, isTrue);
+
+    Actions.invoke(focusWidget.focusNode!.context!, const ActivateIntent());
+    await tester.pump();
+    expect(find.bySemanticsLabel('Activity, 2 steps, expanded'), findsOneWidget);
+  });
+}

test/goldens/holder_card_goldens_test.dart

@@ -0,0 +1,66 @@
+import 'package:alchemist/alchemist.dart';
+import 'package:clide/builtin/claude/src/conversation_card.dart';
+import 'package:clide/builtin/claude/src/holder_card.dart';
+import 'package:flutter/widgets.dart';
+import 'package:flutter_test/flutter_test.dart';
+
+import '../helpers/kernel_fixture.dart';
+import '../helpers/widget_harness.dart';
+
+void main() {
+  late KernelFixture f;
+
+  setUp(() async => f = await KernelFixture.create());
+  tearDown(() async => f.dispose());
+
+  goldenTest(
+    'ClideHolderCard (T-266): collapsed ticker + expanded container of sub-cards',
+    fileName: 'holder_card',
+    builder: () => GoldenTestGroup(
+      columns: 1,
+      children: [
+        GoldenTestScenario(
+          name: 'collapsed (ticker + step count)',
+          child: _wrap(
+            f,
+            const ClideHolderCard(
+              collapsedSummary: 'Bash  ls -la',
+              stepLabel: '3 steps',
+              children: [],
+            ),
+          ),
+        ),
+        GoldenTestScenario(
+          name: 'expanded (framed container wrapping sub-cards)',
+          child: _wrap(
+            f,
+            const ClideHolderCard(
+              collapsedSummary: 'Bash  ls -la',
+              stepLabel: '3 steps',
+              initiallyExpanded: true,
+              children: [
+                ConversationCard(
+                  variant: ConversationCardVariant.bordered,
+                  accent: Color(0xFF4C9AFF),
+                  label: 'Bash',
+                  body: Text('ls -la', textDirection: TextDirection.ltr),
+                ),
+                ConversationCard(
+                  variant: ConversationCardVariant.bordered,
+                  accent: Color(0xFF4C9AFF),
+                  label: 'Read',
+                  body: Text('/lib/main.dart', textDirection: TextDirection.ltr),
+                ),
+              ],
+            ),
+          ),
+        ),
+      ],
+    ),
+  );
+}
+
+Widget _wrap(KernelFixture f, Widget child) => SizedBox(
+      width: 360,
+      child: harness(f, child),
+    );