Add end-to-end auth session widget flow test

docs/progress.md

@@ -2,6 +2,25 @@
 
 Updated: 2026-02-15
 
+## Latest Milestone (2026-02-15): App Session Flow Test Coverage
+
+Added higher-level widget coverage for a core authenticated user journey:
+
+- New test:
+  - `test/features/app/app_auth_flow_test.dart`
+  - validates end-to-end path:
+    - sign-in screen shown by default
+    - sign-in transitions into app shell
+    - navigate to settings and sign out
+    - sign-out returns to sign-in screen
+- Uses deterministic in-memory overrides for token, local data store, sync state
+  store, and backend gateway fake.
+
+Validation for this milestone:
+
+- `flutter analyze` -> pass
+- `flutter test` -> pass
+
 ## Latest Milestone (2026-02-15): Rejected-Mutation Requeue Flow
 
 Extended sync conflict handling so rejected mutations can be retried after local