docs(phase-4): add validation strategy

.planning/phases/04-notifications/04-VALIDATION.md

@@ -0,0 +1,80 @@
+---
+phase: 4
+slug: notifications
+status: draft
+nyquist_compliant: false
+wave_0_complete: false
+created: 2026-03-16
+---
+
+# Phase 4 — Validation Strategy
+
+> Per-phase validation contract for feedback sampling during execution.
+
+---
+
+## Test Infrastructure
+
+| Property | Value |
+|----------|-------|
+| **Framework** | flutter_test (built-in) |
+| **Config file** | none — uses flutter test runner |
+| **Quick run command** | `flutter test test/core/notifications/` |
+| **Full suite command** | `flutter test` |
+| **Estimated runtime** | ~15 seconds |
+
+---
+
+## Sampling Rate
+
+- **After every task commit:** Run `flutter test test/core/notifications/`
+- **After every plan wave:** Run `flutter test`
+- **Before `/gsd:verify-work`:** Full suite must be green + `dart analyze --fatal-infos`
+- **Max feedback latency:** 15 seconds
+
+---
+
+## Per-Task Verification Map
+
+| Task ID | Plan | Wave | Requirement | Test Type | Automated Command | File Exists | Status |
+|---------|------|------|-------------|-----------|-------------------|-------------|--------|
+| 04-01-01 | 01 | 1 | NOTF-01 | unit | `flutter test test/core/notifications/notification_service_test.dart` | ❌ W0 | ⬜ pending |
+| 04-01-02 | 01 | 1 | NOTF-01 | unit | `flutter test test/core/notifications/notification_service_test.dart` | ❌ W0 | ⬜ pending |
+| 04-01-03 | 01 | 1 | NOTF-02 | unit | `flutter test test/core/notifications/notification_settings_notifier_test.dart` | ❌ W0 | ⬜ pending |
+| 04-01-04 | 01 | 1 | NOTF-02 | unit | `flutter test test/core/notifications/notification_settings_notifier_test.dart` | ❌ W0 | ⬜ pending |
+
+*Status: ⬜ pending · ✅ green · ❌ red · ⚠️ flaky*
+
+---
+
+## Wave 0 Requirements
+
+- [ ] `test/core/notifications/notification_service_test.dart` — stubs for NOTF-01 scheduling logic
+- [ ] `test/core/notifications/notification_settings_notifier_test.dart` — stubs for NOTF-02 persistence
+- [ ] `lib/core/notifications/notification_service.dart` — service stub for testing
+- [ ] `android/app/build.gradle.kts` — add desugaring dependency
+- [ ] `android/app/src/main/AndroidManifest.xml` — permissions + receivers
+- [ ] Framework install: `flutter pub add flutter_local_notifications timezone flutter_timezone`
+
+---
+
+## Manual-Only Verifications
+
+| Behavior | Requirement | Why Manual | Test Instructions |
+|----------|-------------|------------|-------------------|
+| Boot receiver manifest entry present (exported=true) | NOTF-01 | Static XML config, not runtime testable | Inspect AndroidManifest.xml for `ScheduledNotificationBootReceiver` with `android:exported="true"` |
+| POST_NOTIFICATIONS permission requested on toggle-on | NOTF-01 | Native Android permission dialog | Run on Android 13+ emulator, toggle notification ON, verify dialog appears |
+| Notification actually appears on device | NOTF-01 | flutter_local_notifications dispatches to native | Run on emulator, schedule notification 1 min ahead, verify it appears |
+
+---
+
+## Validation Sign-Off
+
+- [ ] All tasks have `<automated>` verify or Wave 0 dependencies
+- [ ] Sampling continuity: no 3 consecutive tasks without automated verify
+- [ ] Wave 0 covers all MISSING references
+- [ ] No watch-mode flags
+- [ ] Feedback latency < 15s
+- [ ] `nyquist_compliant: true` set in frontmatter
+
+**Approval:** pending