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+---
+phase: 8
+slug: mobile-pwa
+status: draft
+nyquist_compliant: false
+wave_0_complete: false
+created: 2026-03-26
+---
+
+# Phase 8 — Validation Strategy
+
+> Per-phase validation contract for feedback sampling during execution.
+
+---
+
+## Test Infrastructure
+
+| Property | Value |
+|----------|-------|
+| **Framework** | ESLint + TypeScript strict + Next.js build (existing) |
+| **Config file** | `eslint.config.mjs`, `tsconfig.json` |
+| **Quick run command** | `cd packages/portal && npm run lint` |
+| **Full suite command** | `cd packages/portal && npm run build` |
+| **Estimated runtime** | ~45 seconds |
+
+---
+
+## Sampling Rate
+
+- **After every task commit:** Run `npm run lint` in packages/portal
+- **After every plan wave:** Run `npm run build` in packages/portal
+- **Before `/gsd:verify-work`:** Full build must pass + Lighthouse PWA audit score >= 90
+- **Max feedback latency:** 45 seconds
+
+---
+
+## Per-Task Verification Map
+
+| Task ID | Plan | Wave | Requirement | Test Type | Automated Command | File Exists | Status |
+|---------|------|------|-------------|-----------|-------------------|-------------|--------|
+| 08-xx | 01 | 0 | MOB-04 | build | `npx next build` | ✅ | ⬜ pending |
+| 08-xx | 02 | 1 | MOB-01,02 | build | `npx next build` | ✅ | ⬜ pending |
+| 08-xx | 03 | 1 | MOB-03 | build | `npx next build` | ✅ | ⬜ pending |
+| 08-xx | 04 | 2 | MOB-04,05 | build | `npx next build` | ✅ | ⬜ pending |
+| 08-xx | 05 | 2 | MOB-06 | build | `npx next build` | ✅ | ⬜ pending |
+
+*Status: ⬜ pending · ✅ green · ❌ red · ⚠️ flaky*
+
+---
+
+## Wave 0 Requirements
+
+- [ ] `public/icon-192.png` — K monogram icon (192x192)
+- [ ] `public/icon-512.png` — K monogram icon (512x512)
+- [ ] `public/icon-maskable-192.png` — Maskable variant with safe-zone padding
+- [ ] `public/apple-touch-icon.png` — iOS home screen icon (180x180)
+- [ ] `public/badge-72.png` — Notification badge (72x72, monochrome)
+- [ ] VAPID keys generated and added to `.env`
+- [ ] `npm install @serwist/next serwist web-push idb` + `npm install -D @types/web-push`
+
+---
+
+## Manual-Only Verifications
+
+| Behavior | Requirement | Why Manual | Test Instructions |
+|----------|-------------|------------|-------------------|
+| Pages render at 320px–1024px | MOB-01 | Device emulation | Chrome DevTools device mode, check all pages |
+| Bottom tab bar on mobile | MOB-02 | Visual layout | Resize below 768px, verify tabs appear |
+| Chat full-screen on mobile | MOB-03 | UI interaction | Tap conversation, verify full-screen with back arrow |
+| PWA installable | MOB-04 | Browser behavior | Lighthouse PWA audit, manual install from Chrome |
+| Push notification received | MOB-05 | Requires HTTPS + real device | Install PWA, send test message, verify notification |
+| No hover-stuck interactions | MOB-06 | Touch device | Tap all buttons/links on real touch device |
+
+---
+
+## 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 < 45s
+- [ ] `nyquist_compliant: true` set in frontmatter
+
+**Approval:** pending