fix(idle): hold idle while the workspace trust dialog is on screen

The dialog's own prompt glyph armed idle confirmation and the quiet dialog passed it, so a fresh case reported idle about 4 s in. An agent that waited for idle and then prompted typed into the dialog, and its Enter confirmed No, exit and killed the pane.

test/session-trust-dialog.test.ts

@@ -16,6 +16,17 @@
  */
 import { describe, expect, it, vi, afterEach } from 'vitest';
 import { Session } from '../src/session.js';
+
+// The restart case below starts a real direct-PTY session; the real `claude` must never
+// run from a test, so pty.spawn runs a harmless stand-in instead.
+vi.mock('node-pty', async (importOriginal) => {
+  const real = await importOriginal<typeof import('node-pty')>();
+  return {
+    ...real,
+    spawn: (_file: string, _args: string[] | string, options: import('node-pty').IPtyForkOptions) =>
+      real.spawn(process.execPath, ['-e', 'setInterval(() => {}, 1000)'], options),
+  };
+});
 import {
   isTrustDialogScreen,
   compactScreenText,
@@ -249,3 +260,104 @@ describe('Session trust-dialog auto-accept', () => {
     expect(writes).toEqual([]);
   });
 });
+
+describe('Session idle detection while the trust dialog is up', () => {
+  afterEach(() => vi.useRealTimers());
+
+  /** A just-launched pane (busy, inside the startup window) rendering `screen` (null: capture failed). */
+  function launchingSession(screen: () => string | null) {
+    const mux = { isAvailable: () => true, capturePaneText: () => screen() };
+    const session = new Session({
+      workingDir: '/tmp',
+      mode: 'claude',
+      mux,
+      muxSession: { muxName: 'codeman-test', sessionId: 'test', createdAt: Date.now() },
+    } as unknown as ConstructorParameters<typeof Session>[0]);
+    const internals = session as unknown as {
+      _detectInteractiveActivity(data: string): void;
+      _markActivity(): void;
+      _interactiveStartedAt: number;
+      _status: string;
+    };
+    internals._interactiveStartedAt = Date.now();
+    internals._status = 'busy'; // what startInteractive() leaves a new pane at
+    let idles = 0;
+    session.on('idle', () => idles++);
+    /** One repaint carrying a `❯`, which is what arms the idle confirmation. */
+    const paint = (chunk: string) => {
+      internals._markActivity();
+      internals._detectInteractiveActivity(chunk);
+    };
+    return { session, paint, idles: () => idles };
+  }
+
+  it('does not call the dialog idle, although its own ❯ arms the check', () => {
+    vi.useFakeTimers();
+    const { session, paint, idles } = launchingSession(() => RENDERED_DIALOG_2_1_252);
+    paint(RENDERED_DIALOG_2_1_252);
+    vi.advanceTimersByTime(30_000);
+    expect(session.status).toBe('busy');
+    expect(idles()).toBe(0);
+  });
+
+  it('goes idle once the dialog has been answered and the composer is up', () => {
+    vi.useFakeTimers();
+    let screen = RENDERED_DIALOG_2_1_252;
+    const { session, paint, idles } = launchingSession(() => screen);
+    paint(RENDERED_DIALOG_2_1_252);
+    vi.advanceTimersByTime(10_000);
+    expect(session.status).toBe('busy');
+
+    // No new output needed: the check keeps re-reading the screen on its own.
+    screen = RENDERED_MAIN_UI.replace('✻ Actualizing… (13m 23s · ↓ 47.5k tokens)', '');
+    vi.advanceTimersByTime(10_000);
+    expect(session.status).toBe('idle');
+    expect(idles()).toBe(1);
+  });
+
+  it('keeps holding when a capture fails after the dialog was seen', () => {
+    vi.useFakeTimers();
+    // A failed capture says nothing about whether the dialog went away.
+    let screen: string | null = RENDERED_DIALOG_2_1_252;
+    const { session, paint, idles } = launchingSession(() => screen);
+    paint(RENDERED_DIALOG_2_1_252);
+    vi.advanceTimersByTime(5000);
+    screen = null;
+    vi.advanceTimersByTime(20_000);
+    expect(session.status).toBe('busy');
+    expect(idles()).toBe(0);
+  });
+
+  it("does not carry the last pane's dialog verdict into a restarted pane", async () => {
+    // The session saw the dialog on its last pane, then restarted where no capture can
+    // replace that verdict (here the direct-PTY fallback, which has no pane to read; a
+    // failed capture keeps it the same way). The new pane must still be able to go idle.
+    const session = new Session({ workingDir: '/tmp', mode: 'claude', useMux: false });
+    (session as unknown as { _lastPaneProbeTrustDialog: boolean })._lastPaneProbeTrustDialog = true;
+    try {
+      await session.startInteractive();
+      vi.useFakeTimers();
+      const internals = session as unknown as {
+        _detectInteractiveActivity(data: string): void;
+        _markActivity(): void;
+      };
+      internals._markActivity();
+      internals._detectInteractiveActivity('❯ ');
+      vi.advanceTimersByTime(30_000);
+      expect(session.status).toBe('idle');
+    } finally {
+      vi.useRealTimers();
+      await session.stop();
+    }
+  });
+
+  it('lets a dialog-looking screen go idle outside the startup window', () => {
+    vi.useFakeTimers();
+    // A live agent can print the dialog's words hours in, and must not be held busy.
+    const { session, paint } = launchingSession(() => RENDERED_DIALOG_2_1_252);
+    vi.advanceTimersByTime(10 * 60_000);
+    paint(RENDERED_DIALOG_2_1_252);
+    vi.advanceTimersByTime(30_000);
+    expect(session.status).toBe('idle');
+  });
+});