feat(crash): comprehensive crash + error reporting for v0.2.3

Adds full-stack crash capture so any unexpected failure — React render,
uncaught JS exception, unhandled promise rejection, or native — is
reported to Sentry with rich, scrubbed context. Expected operational
errors (timeouts, biometric cancel, etc.) stay local to preserve signal.

Changes:
- src/lib/sentry.ts: explicit native crash handlers, release/dist tags
  from app.json, beforeSend/beforeBreadcrumb URL+secret scrubbing,
  addBreadcrumb/captureException helpers, ErrorUtils + onunhandledrejection
  wrappers that always feed the in-memory log buffer (so offline Share
  Report includes the crash too).
- src/components/ErrorBoundary.tsx: new app-wide React boundary with a
  dark recovery screen — error message, top stack/component frames,
  Share Report (clipboard + native share sheet) and Try Again.
- src/lib/diagnostics.ts: buildCrashReport() reuses the existing
  DiagnosticReport pipeline so crashes and connect failures share one
  UI and one transport.
- _layout.tsx: wraps app in ErrorBoundary; emits app.lifecycle
  breadcrumb at startup.
- stores/{connections,events,sessions}.ts: high-signal breadcrumbs at
  connect, SSE connect/disconnect/reconnect, and session select.
- (tabs)/settings.tsx: fix unhandled promise on notificationsGranted().
- app.json: bump expo.version to 0.2.3.
- docs/prd.md, docs/tdd.md: new product + technical design docs.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

app/(tabs)/settings.tsx

@@ -94,7 +94,9 @@ export default function SettingsScreen() {
 
   // Lazy-check OS permission for status display
   if (osGranted === null) {
-    notificationsGranted().then(setOsGranted)
+    notificationsGranted()
+      .then(setOsGranted)
+      .catch(() => setOsGranted(false))
   }
 
   return (

app/_layout.tsx

@@ -11,10 +11,12 @@ import { useEvents } from "../src/stores/events"
 import { useCatalog } from "../src/stores/catalog"
 import { useSettings } from "../src/stores/settings"
 import { AuthGate } from "../src/components/AuthGate"
+import { ErrorBoundary } from "../src/components/ErrorBoundary"
 import * as notifications from "../src/lib/notifications"
-import { initSentry, wrap } from "../src/lib/sentry"
+import { addBreadcrumb, initSentry, wrap } from "../src/lib/sentry"
 
 initSentry()
+addBreadcrumb({ category: "app.lifecycle", message: "app started" })
 
 const queryClient = new QueryClient()
 
@@ -76,10 +78,11 @@ function RootLayout() {
   }
 
   return (
-    <GestureHandlerRootView style={{ flex: 1 }}>
-      <BottomSheetModalProvider>
-        <QueryClientProvider client={queryClient}>
-          <AuthGate>
+    <ErrorBoundary>
+      <GestureHandlerRootView style={{ flex: 1 }}>
+        <BottomSheetModalProvider>
+          <QueryClientProvider client={queryClient}>
+            <AuthGate>
             <Stack
               screenOptions={{
                 headerStyle: {
@@ -114,11 +117,12 @@ function RootLayout() {
                 }}
               />
             </Stack>
-            <StatusBar style={isDark ? "light" : "dark"} />
-          </AuthGate>
-        </QueryClientProvider>
-      </BottomSheetModalProvider>
-    </GestureHandlerRootView>
+              <StatusBar style={isDark ? "light" : "dark"} />
+            </AuthGate>
+          </QueryClientProvider>
+        </BottomSheetModalProvider>
+      </GestureHandlerRootView>
+    </ErrorBoundary>
   )
 }