docs(phase-8): complete Mobile + PWA phase execution

Fixed uuid() recursion bug, updated MOB-02 requirement text.
All 8 phases complete.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

.planning/STATE.md

@@ -4,7 +4,7 @@ milestone: v1.0
 milestone_name: milestone
 status: completed
 stopped_at: Completed 08-mobile-pwa 08-04-PLAN.md — Phase 08 and v1.0 milestone complete
-last_updated: "2026-03-26T03:33:24.019Z"
+last_updated: "2026-03-26T03:38:45.402Z"
 last_activity: 2026-03-23 — Completed 03-02 onboarding wizard, Slack OAuth, BYO API keys
 progress:
   total_phases: 8