Activity tab: session controls + live usage block (T-415)

The Activity tab gains the power-panel's session strip and a usage block:

- SESSION controls (clear / compact / fork / resume + refresh-usage)
  publish their slash command on builtin.claude/command — the same path
  as typing it, so /clear semantics (and any future confirm behavior)
  live in exactly one place.
- The usage block revisits T-158's "blocked on upstream": probed against
  claude 2.1.175, a forwarded /usage IS answered headless, free
  (num_turns 0), as parseable text. parseUsageText() extracts session /
  week / week-Sonnet percentages (timezone parentheticals stripped); the
  sidebar watches the primary session's synthetic output for
  usage-shaped responses and renders them as a USAGE section. Refresh is
  user-initiated (the control sends /usage) — no polling, no background
  calls (D-64).
- The runtime row gains the session's effort level (T-412's status
  field).

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

lib/builtin/claude/src/meta_sidebar/activity_tab.dart

@@ -1,28 +1,47 @@
-/// The Activity tab: usage stats (stats-cache.json) + the primary
-/// session's live runtime row. Split out of claude_meta_sidebar.dart
-/// (T-395).
+/// The Activity tab: session controls, usage, stats (stats-cache.json), and
+/// the primary session's live runtime row. Split out of
+/// claude_meta_sidebar.dart (T-395); session controls + the usage block are
+/// the power-panel additions (T-415).
 library;
 
 import 'package:clide/builtin/claude/src/claude_config.dart';
 import 'package:clide/builtin/claude/src/claude_stats.dart';
-import 'package:clide/builtin/claude/src/claude_status.dart' show formatTokenCount, permissionModeLabel, shortModelLabel;
+import 'package:clide/builtin/claude/src/claude_status.dart' show ClaudeUsage, formatTokenCount, permissionModeLabel, shortModelLabel;
 import 'package:clide/builtin/claude/src/meta_sidebar/models.dart';
 import 'package:clide/builtin/claude/src/transcript_reader.dart' show SessionStatus;
 import 'package:clide/kernel/kernel.dart';
+import 'package:clide/widgets/widgets.dart';
 import 'package:flutter/widgets.dart';
 
 class ActivityTabView extends StatelessWidget {
-  const ActivityTabView({super.key, required this.stats, required this.primaryStatus, required this.config});
+  const ActivityTabView({super.key, required this.stats, required this.primaryStatus, required this.config, this.usage});
 
   final ClaudeStats stats;
   final SessionStatus? primaryStatus;
   final ClaudeConfig? config;
 
+  /// Parsed `/usage` output for the usage block, refreshed via the refresh
+  /// control (T-415). Null until the first refresh.
+  final ClaudeUsage? usage;
+
+  /// Publish a slash command for the primary pane to execute — the session
+  /// controls are the same code path as typing the command (D-6).
+  void _command(BuildContext context, String text) {
+    ClideKernel.of(context).messages.publish('builtin.claude', 'command', {'text': text});
+  }
+
   @override
   Widget build(BuildContext context) {
     final tokens = ClideTheme.of(context).surface;
     final latest = stats.latest;
+    final u = usage;
     final sections = <MetaSection>[
+      if (u != null)
+        MetaSection('USAGE', [
+          if (u.session != null) MetaRow('session', u.session!),
+          if (u.week != null) MetaRow('week (all)', u.week!),
+          if (u.weekSonnet != null) MetaRow('week (sonnet)', u.weekSonnet!),
+        ]),
       if (latest != null)
         MetaSection('TODAY', [
           MetaRow('messages', '${latest.messageCount}'),
@@ -32,10 +51,47 @@ class ActivityTabView extends StatelessWidget {
       if (latest != null) MetaSection('LIFETIME', [MetaRow('messages', '${stats.lifetimeMessages}'), MetaRow('sessions', '${stats.lifetimeSessions}')]),
       ..._runtimeSection(tokens),
     ];
-    if (sections.isEmpty) {
-      return metaPlaceholder('No activity recorded yet.');
-    }
-    return buildMetaTable(tokens, sections);
+
+    return ListView(
+      padding: const EdgeInsets.all(12),
+      children: [
+        // SESSION control strip (T-415): drives the primary session through
+        // the builtin.claude/command bus — identical to typing the command.
+        Padding(
+          padding: const EdgeInsets.only(bottom: 8),
+          child: ClideText('SESSION', fontSize: clideFontSmall, color: tokens.sidebarSectionHeader),
+        ),
+        Row(
+          children: [
+            _control(context, tokens, 'clear', 'trash', '/clear'),
+            _control(context, tokens, 'compact', 'arrows-in-simple', '/compact'),
+            _control(context, tokens, 'fork', 'git-branch', '/fork'),
+            _control(context, tokens, 'resume', 'clock-counter-clockwise', '/resume'),
+            const Spacer(),
+            _control(context, tokens, 'refresh usage', 'arrow-clockwise', '/usage'),
+          ],
+        ),
+        const SizedBox(height: 6),
+        if (sections.isEmpty) metaPlaceholder('No activity recorded yet.') else ...metaTableChildren(tokens, sections),
+      ],
+    );
+  }
+
+  Widget _control(BuildContext context, SurfaceTokens tokens, String label, String glyph, String command) {
+    return Semantics(
+      button: true,
+      label: '$label session',
+      excludeSemantics: true,
+      onTap: () => _command(context, command),
+      child: ClideTappable(
+        tooltip: '$label  ·  $command',
+        onTap: () => _command(context, command),
+        builder: (ctx, hovered, _) => Padding(
+          padding: const EdgeInsets.symmetric(horizontal: 6, vertical: 2),
+          child: ClideIcon(PhosphorIcons.byName(glyph), size: 15, color: hovered ? tokens.globalForeground : tokens.globalTextMuted),
+        ),
+      ),
+    );
   }
 
   List<MetaSection> _runtimeSection(SurfaceTokens tokens) {
@@ -43,6 +99,7 @@ class ActivityTabView extends StatelessWidget {
     final skills = config?.skills.length;
     final rows = <MetaRow>[
       if (st?.model != null) MetaRow('model', shortModelLabel(st!.model!), valueColor: tokens.globalFocus),
+      if (st?.effort != null) MetaRow('effort', st!.effort!),
       if (st?.contextTokens != null) MetaRow('context', '${formatTokenCount(st!.contextTokens!)} ctx'),
       if (st?.permissionMode != null) MetaRow('mode', permissionModeLabel(st!.permissionMode!)),
       if (skills != null) MetaRow('skills', '$skills'),

lib/builtin/claude/src/meta_sidebar/models.dart

@@ -44,7 +44,12 @@ Widget metaPlaceholder(String text) => Padding(
 );
 
 /// Key→value sections on the shared table geometry (Activity + Config).
-Widget buildMetaTable(SurfaceTokens tokens, List<MetaSection> sections) {
+Widget buildMetaTable(SurfaceTokens tokens, List<MetaSection> sections) =>
+    ListView(padding: const EdgeInsets.all(12), children: metaTableChildren(tokens, sections));
+
+/// The table rows without the enclosing ListView, for tabs that compose extra
+/// widgets around the sections (the Activity tab's control strip, T-415).
+List<Widget> metaTableChildren(SurfaceTokens tokens, List<MetaSection> sections) {
   final children = <Widget>[];
   for (var i = 0; i < sections.length; i++) {
     final s = sections[i];
@@ -74,5 +79,5 @@ Widget buildMetaTable(SurfaceTokens tokens, List<MetaSection> sections) {
       );
     }
   }
-  return ListView(padding: const EdgeInsets.all(12), children: children);
+  return children;
 }