feat(tui): add subagent runtime behavior

Summary:\n- add the live subagent and watchdog runtime panel on top of the inbox foundation work\n- keep the subagent panel pinned and out of transcript history\n- mount the panel independently of the active transcript cell and render watchdog handles with the expected idle labeling\n\nTesting:\n- just fmt\n- cargo test -p codex-tui subagent_panel_is_not_flushed_into_transcript_history -- --exact\n- cargo test -p codex-tui subagent_panel_mounts_while_placeholder_active_cell_exists_snapshot -- --exact\n- cargo test -p codex-tui subagent_panel_renders_watchdog_handle_as_idle -- --exact\n- just fix -p codex-tui

Author: friel-openai

codex-rs/.config/nextest.toml

@@ -27,3 +27,9 @@ test-group = 'app_server_protocol_codegen'
 # Keep the library unit tests parallel.
 filter = 'package(codex-app-server) & kind(test)'
 test-group = 'app_server_integration'
+
+[[profile.default.overrides]]
+# Schema fixture generation can take longer than the default timeout on slower
+# Windows runners when app-server protocol fixture sets grow.
+filter = 'test(schema_fixtures_match_generated)'
+slow-timeout = { period = "1m", terminate-after = 2 }

codex-rs/app-server/tests/suite/v2/thread_unsubscribe.rs

@@ -192,6 +192,10 @@ async fn thread_unsubscribe_during_turn_interrupts_turn_and_emits_thread_closed(
         wait_for_command_execution_item_started(&mut mcp),
     )
     .await??;
+    // `item/started` can arrive before the spawned command reports a process id.
+    // Give the runtime a brief moment to finish wiring the command so unsubscribe
+    // consistently exercises the shutdown path on slower CI runners.
+    tokio::time::sleep(std::time::Duration::from_millis(250)).await;
 
     let unsubscribe_id = mcp
         .send_thread_unsubscribe_request(ThreadUnsubscribeParams {