assembly live: exit cleanly on Ctrl-C during TUI setup

A Ctrl-C during the voice TUI's setup — opening the mic, building the deepagents
graph, loading --mcp-config servers — lands before Textual captures the keyboard,
so it surfaced as a raw KeyboardInterrupt (and, mid asyncio.run/threading
teardown, a noisy traceback). The line-renderer path already mapped this to a
clean exit 130; the TUI dispatch did not. Extract a _launch_tui helper that wraps
_run_live_tui and maps a setup-time KeyboardInterrupt to typer.Exit(130), matching
the assembly code TUI. (In-session Ctrl-C is already a Textual binding, so it never
reaches the graph as an exception.)

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

Author: alexkroman-assembly

aai_cli/commands/agent_cascade/_exec.py

@@ -247,6 +247,20 @@ def run_conversation(renderer: engine.Renderer) -> None:
     app.run(mouse=False)
 
 
+def _launch_tui(api_key: str, opts: AgentCascadeOptions, config: CascadeConfig) -> None:
+    """Run the voice-only TUI, mapping a setup-time Ctrl-C to a clean exit.
+
+    A Ctrl-C during setup — opening the mic, building the graph, loading ``--mcp-config``
+    servers — lands before Textual captures the keyboard, so it surfaces as a plain
+    ``KeyboardInterrupt`` here. Map it to exit 130 (cancel) rather than letting it dump a
+    half-initialized asyncio/threading traceback.
+    """
+    try:
+        _run_live_tui(api_key, opts, config)
+    except KeyboardInterrupt:
+        raise typer.Exit(code=errors.CANCELLED_EXIT_CODE) from None
+
+
 def run_agent_cascade(opts: AgentCascadeOptions, state: AppState, *, json_mode: bool) -> None:
     """Execute one `assembly agent-cascade` cascade from already-parsed flags."""
     text_mode, json_mode = resolve_output_modes(opts.output_field, json_mode=json_mode)
@@ -290,7 +304,7 @@ def run_agent_cascade(opts: AgentCascadeOptions, state: AppState, *, json_mode:
 
     if _should_use_tui(from_file=from_file, json_mode=json_mode, text_mode=text_mode):
         # The voice-only Textual front-end surfaces the web-search note in-app, not on stderr.
-        _run_live_tui(api_key, opts, config)
+        _launch_tui(api_key, opts, config)
         return
 
     _warn_without_web_search(json_mode=json_mode)

tests/test_live_tui.py

@@ -13,6 +13,7 @@
 import types
 
 import pytest
+import typer
 from textual.widgets import Static
 
 from aai_cli.agent_cascade import engine
@@ -418,6 +419,20 @@ def run(self, **kwargs):
     assert captured["ran"] == {"mouse": False}  # mouse off so transcript text stays selectable
 
 
+def test_tui_setup_keyboard_interrupt_exits_clean(monkeypatch) -> None:
+    # Ctrl-C during TUI setup (mic open / graph build / --mcp-config load) lands before
+    # Textual captures the keyboard; it must exit 130, not surface a raw traceback.
+    _wire_tui(monkeypatch)
+
+    def boom(*_a, **_k):
+        raise KeyboardInterrupt
+
+    monkeypatch.setattr(_exec, "_run_live_tui", boom)
+    with pytest.raises(typer.Exit) as exc:
+        run_agent_cascade(_opts(), AppState(), json_mode=False)
+    assert exc.value.exit_code == 130
+
+
 def test_tui_run_conversation_drives_the_cascade(monkeypatch) -> None:
     # The closure handed to the app runs the cascade with the duplex player and the wired
     # deps, and the cascade's on_session wires the session's reply-interrupt onto the app.