Fix CLI subagent task routing, Ctrl+C cancellation, and session restore reliability

- Construct ServerTask directly for Bedrock CLI subagents so messages route
  correctly without needing a server CreateTask upgrade
- Handle CliAgentUserQuery input type in both request translators, including
  running command context and terminal output
- Add force_cancel_all_streaming_exchanges fallback for when Ctrl+C finds no
  in-flight streams (stuck subagent / unexpected stream end)
- Cancel active conversation on Ctrl+C in agent view compose state
- Skip agent view entry when agent is tagged-in for a running command
- Set root_task_id on Bedrock requests for proper optimistic task upgrade
- Persist app state on will_terminate to avoid losing sessions
- Trust persisted CWD without is_dir() recheck (fixes network mount restore)
- Log warning instead of silently dropping tabs with unreadable root nodes

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

app/src/lib.rs

@@ -1866,6 +1866,11 @@ fn app_callbacks(is_integration_test: bool) -> galaxyui::platform::AppCallbacks
             );
         })),
         on_will_terminate: Some(Box::new(move |ctx| {
+            // Persist the final app state before tearing down the writer.
+            // This ensures the latest session (tabs, CWD, conversations) is saved
+            // even if the termination bypassed individual window-close events.
+            ctx.dispatch_global_action("workspace:save_app", &());
+
             NotebookManager::handle(ctx).update(ctx, |manager, ctx| {
                 // Notebooks are only saved periodically, so ensure that any pending changes have
                 // been sent to the writer thread before terminating.