decouple Pane from PtySession so the web build compiles

Pane is now a pure data class — id, kind, pid, argv, cwd, title,
isClosed. The daemon-side PaneRegistry holds a parallel map of
PtySession keyed on id; registry methods look up both sides when
writing / resizing / closing.

The `clide.dart` barrel no longer re-exports `src/pty/*`,
`src/panes/registry.dart`, or the `*_commands.dart` modules — all
three transitively import `dart:ffi` which isn't available when
compiling to WebAssembly. The daemon entrypoint (bin/clide.dart) +
core tests import them via deep paths now. Pane / PaneKind /
DaemonEventSink / RecordingEventSink stay in the barrel since
they're pure data the Flutter app references over IPC.

Verified: `dart analyze` clean, 53 core tests green, 174 app tests
green, `make ui-smoke` compiles + serves + Playwright smoke passes,
daemon boots + ping round-trips + SIGTERMs cleanly.

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

bin/clide.dart

@@ -13,6 +13,12 @@ import 'dart:convert';
 import 'dart:io';
 
 import 'package:clide/clide.dart';
+// Daemon-only deep imports — these pull in dart:ffi (PTY) and
+// daemon-subsystem wiring that the Flutter app doesn't need and
+// can't compile for web. See lib/clide.dart for the barrel split.
+import 'package:clide/src/daemon/files_commands.dart';
+import 'package:clide/src/daemon/pane_commands.dart';
+import 'package:clide/src/panes/registry.dart';
 
 Future<void> main(List<String> argv) async {
   if (argv.isEmpty) {

lib/clide.dart

@@ -8,21 +8,23 @@
 ///   * `decisions/architecture.md` `D-006` — CLI + event contract.
 library;
 
+// Flutter-app-visible surface. Deliberately **does not** export the
+// `pty/` or `panes/registry.dart` modules — those import `dart:ffi`
+// and pull in the PTY machinery that only runs on desktop. The
+// daemon entrypoint (`bin/clide.dart`) imports them via deep paths.
+//
+// `Pane` + `PaneKind` + the event-sink interfaces travel here because
+// they're pure data types that both the app and the daemon reference.
+
 export 'src/daemon/dispatcher.dart';
-export 'src/daemon/files_commands.dart';
-export 'src/daemon/pane_commands.dart';
 export 'src/files/ignore.dart';
 export 'src/files/listing.dart' show FileEntry, listDir;
-export 'src/files/watcher.dart';
 export 'src/ipc/envelope.dart';
 export 'src/ipc/paths.dart';
 export 'src/ipc/schema_v1.dart';
 export 'src/ipc/server.dart';
 export 'src/panes/event_sink.dart';
 export 'src/panes/pane.dart' show Pane, PaneKind;
-export 'src/panes/registry.dart' show PaneRegistry;
-export 'src/pty/errors.dart' show PtyException;
-export 'src/pty/pty.dart';
 
 /// Build-time-stamped version string.
 ///

lib/src/panes/pane.dart

@@ -1,13 +1,11 @@
-/// A single active pane in the daemon.
+/// A single active pane. Pure data — no PTY coupling so this type
+/// travels cleanly into the Flutter app (which can't depend on
+/// `dart:ffi`-using code for the web build).
 ///
-/// Owns a [PtySession] plus whatever pane-level metadata the UI +
-/// CLI need. The `kind:` field distinguishes general-purpose terminal
-/// panes from Claude panes (D-041, not yet landed) from whatever
-/// future pane-shaped surface Tier 1+ grows.
+/// The daemon's [PaneRegistry] keeps a parallel `PtySession` keyed on
+/// [id] and mutates [isClosed] when the session exits.
 library;
 
-import '../pty/session.dart';
-
 /// Kind of a pane. Keep this enum small and explicit — each kind
 /// typically pairs with a bundled extension that manages its
 /// lifecycle (`builtin.terminal`, `builtin.claude`).
@@ -25,28 +23,28 @@ enum PaneKind {
   }
 }
 
-/// A live pane. Thin wrapper over [PtySession] — the registry is what
-/// owns the session lifecycle; consumers of this class read state and
-/// call [write] / [resize] via the session.
 class Pane {
   Pane({
     required this.id,
     required this.kind,
-    required this.session,
+    required this.pid,
     required this.argv,
     this.cwd,
     this.title,
+    this.isClosed = false,
   });
 
   final String id;
   final PaneKind kind;
-  final PtySession session;
+  final int pid;
   final List<String> argv;
   final String? cwd;
   final String? title;
 
-  int get pid => session.pid;
-  bool get isClosed => session.isClosed;
+  /// Mutated by the registry when the child exits or the session
+  /// closes. Kept mutable so registry state doesn't need to replace
+  /// [Pane] instances on transition.
+  bool isClosed;
 
   Map<String, Object?> toJson() => {
         'id': id,

lib/src/panes/registry.dart

@@ -20,6 +20,7 @@ class PaneRegistry {
 
   final DaemonEventSink events;
   final Map<String, Pane> _panes = {};
+  final Map<String, PtySession> _sessions = {};
   final Map<String, StreamSubscription<Uint8List>> _subs = {};
   int _nextId = 1;
 
@@ -55,12 +56,13 @@ class PaneRegistry {
     final pane = Pane(
       id: id,
       kind: kind,
-      session: session,
+      pid: session.pid,
       argv: argv,
       cwd: cwd,
       title: title,
     );
     _panes[id] = pane;
+    _sessions[id] = session;
 
     _emit('pane.spawned', id, pane.toJson());
 
@@ -77,15 +79,17 @@ class PaneRegistry {
   /// Send bytes to a pane's stdin.
   int write(String id, List<int> bytes) {
     final p = _panes[id];
-    if (p == null || p.isClosed) return 0;
-    return p.session.write(bytes);
+    final s = _sessions[id];
+    if (p == null || p.isClosed || s == null) return 0;
+    return s.write(bytes);
   }
 
   /// Resize a pane + emit `pane.resized`.
   void resize(String id, {required int cols, required int rows}) {
     final p = _panes[id];
-    if (p == null || p.isClosed) return;
-    p.session.resize(cols: cols, rows: rows);
+    final s = _sessions[id];
+    if (p == null || p.isClosed || s == null) return;
+    s.resize(cols: cols, rows: rows);
     _emit('pane.resized', id, {'cols': cols, 'rows': rows});
   }
 
@@ -93,9 +97,11 @@ class PaneRegistry {
   Future<void> close(String id) async {
     final p = _panes[id];
     if (p == null) return;
-    await p.session.close();
+    final s = _sessions[id];
+    if (s != null) await s.close();
     await _subs[id]?.cancel();
     _subs.remove(id);
+    _sessions.remove(id);
     _panes.remove(id);
     _emit('pane.closed', id, const {});
   }
@@ -111,6 +117,7 @@ class PaneRegistry {
 
   void _onExit(Pane p) {
     if (_panes.containsKey(p.id)) {
+      p.isClosed = true;
       _emit('pane.exit', p.id, const {});
       // Don't auto-close — keep the pane entry so `list` can show the
       // exited state until the consumer explicitly closes. A future

test/daemon/files_commands_test.dart

@@ -4,6 +4,7 @@ library;
 import 'dart:io';
 
 import 'package:clide/clide.dart';
+import 'package:clide/src/daemon/files_commands.dart';
 import 'package:test/test.dart';
 
 void main() {

test/daemon/pane_commands_test.dart

@@ -9,6 +9,8 @@ import 'dart:convert';
 import 'dart:io';
 
 import 'package:clide/clide.dart';
+import 'package:clide/src/daemon/pane_commands.dart';
+import 'package:clide/src/panes/registry.dart';
 import 'package:test/test.dart';
 
 void main() {

test/panes/registry_test.dart

@@ -10,6 +10,7 @@ import 'dart:convert';
 import 'dart:io';
 
 import 'package:clide/clide.dart';
+import 'package:clide/src/panes/registry.dart';
 import 'package:test/test.dart';
 
 void main() {

test/pty/session_test.dart

@@ -9,7 +9,7 @@ import 'dart:async';
 import 'dart:convert';
 import 'dart:io';
 
-import 'package:clide/clide.dart';
+import 'package:clide/src/pty/pty.dart';
 import 'package:test/test.dart';
 
 void main() {