fix: request notification permission; resync session on focus; notif + reply bugs (#121)

Five correctness bugs from an adversarial review of the notification and
permission/approval paths (each verified against the code):

1. Notifications never worked for most users (HIGH): OS permission was only
   requested when a user manually toggled a Settings switch off→on. Since
   categories default on, that path never fired, permission stayed
   'undetermined', and send() silently no-op'd every notification. Now request
   it once on first live connection (in-context). (app/_layout.tsx)

2. Wrong-session data after back-navigation (HIGH): session screen reads a
   global store and its resync ran only on mount; the native stack keeps
   screens mounted underneath a pushed one, so returning to a session could
   show another session's messages and permission prompts — approving the wrong
   session's tool call. Re-select on focus via useFocusEffect. (app/session/[id].tsx)

3. 'Task completed' fired on aborted/errored runs (misleading, and a duplicate
   push alongside 'Session error'). Gate the notify by !aborted && !errored.
   (src/stores/events.ts)

4. Tapping a connection-drop notification (no sessionId) navigated to an empty
   '/session/' dead-end. Route to home instead. (app/_layout.tsx)

5. Double-tap on a single-select question sent two replies; the second hit an
   already-resolved request and popped a spurious 'Reply failed' alert. One-shot
   guard on reply/reject. (src/components/chat/QuestionPrompt.tsx)

Verified but intentionally NOT changed: 'completed' notifications default off
(a defensible anti-spam choice — the app still notifies when the agent needs
input). typecheck clean, 187/187 tests.


Claude-Session: https://claude.ai/code/session_01T12AhSnQVrSxNnvwfCx2z6

Co-authored-by: engineer <engineer@macbookpro.lan>
Co-authored-by: Claude Fable 5 <noreply@anthropic.com>

app/_layout.tsx

@@ -30,6 +30,7 @@ function RootLayout() {
   const { initialize: initAuth, isLoading: authLoading } = useAuth()
   const { loadConnections, isLoading: connectionsLoading, client } = useConnections()
   const sseStarted = useRef(false)
+  const notifPermissionRequested = useRef(false)
 
   // Telemetry consent state: null = loading, 'unknown' = show modal, else decided
   const [consentState, setConsentState] = useState<"loading" | "unknown" | "decided">("loading")
@@ -42,9 +43,12 @@ function RootLayout() {
     // Connect notification preferences to the notification module
     notifications.configure(() => useSettings.getState().notifications)
 
-    // Navigate to session when user taps a notification
+    // Navigate to session when user taps a notification. Connection-drop
+    // notifications carry no sessionId (they aren't about a session) — route
+    // to the home tab instead of "/session/" (an empty, dead-end route).
     const unsubNotifications = notifications.onTap((data) => {
-      router.push(`/session/${data.sessionId}`)
+      if (data.sessionId) router.push(`/session/${data.sessionId}`)
+      else router.push("/")
     })
 
     // Load telemetry consent — initialise Sentry only if previously granted
@@ -79,6 +83,18 @@ function RootLayout() {
       sseStarted.current = true
       useEvents.getState().connect()
       useCatalog.getState().load()
+      // Request OS notification permission once we have a live connection —
+      // the in-context moment the user will start running agent tasks they'll
+      // want to be pinged about. Previously this was only ever requested when
+      // a user manually toggled a notification switch off→on in Settings; since
+      // most categories default on, that path never fired for typical users
+      // and send() silently no-op'd on every notification (permission stayed
+      // "undetermined"). setup() is idempotent — it won't re-prompt once the
+      // OS has a decision — so the ref just avoids redundant calls per session.
+      if (!notifPermissionRequested.current) {
+        notifPermissionRequested.current = true
+        void notifications.setup()
+      }
     } else if (!client && sseStarted.current) {
       sseStarted.current = false
       useEvents.getState().disconnect()