docs(phase-07): evolve PROJECT.md after phase completion

.planning/PROJECT.md

@@ -57,14 +57,23 @@ desktop for read-only awareness.
   `/api/mobile/analyzer/feed`; existing `/api/analyzer/analyses/[id]` reused
   for detail. No editing, no re-run, no prompt-tuning on mobile. Validated in
   Phase 6: Analyzer Feed (ANL-01..06)
+- ✓ Engagement overview (NEW) — `/mobile/engagement` phone-first refactor
+  reachable from the More drawer (NOT the bottom bar). Sticky 3-chip period
+  selector (7d/30d/90d), 4 stacked summary cards (active users / total Graph
+  hours / total Autotask hours / hours-per-active-user), single-series SVG
+  sparkline (no recharts), sortable per-employee list (Hours/Name/Utilization)
+  with client-side search and IntersectionObserver infinite scroll. Two new
+  endpoints: `/api/mobile/engagement/summary` (totals) and
+  `/api/mobile/engagement/trend` (daily-hours time-series). Existing
+  `/api/engagement/users` reused as-is. Read-only on mobile. Validated in
+  Phase 7: Engagement Overview (ENG-01..05, ENG-09)
 
 ### Active
 
 <!-- Hypotheses for this milestone — see docs/superpowers/specs/2026-05-03-mobile-shell-design.md -->
 
-- [ ] Engagement mobile (NEW) — `/mobile/engagement` overview (period chips,
-      stacked summary cards, sortable per-employee list, sparkline) plus
-      `/mobile/engagement/[userId]` profile page replacing the desktop modal
+- [ ] Engagement user profile (NEW) — `/mobile/engagement/[userId]` real-page
+      profile replacing the desktop modal pattern (Phase 8 — ENG-06..08)
 
 ### Out of Scope
 
@@ -148,4 +157,4 @@ This document evolves at phase transitions and milestone boundaries.
 4. Update Context with current state
 
 ---
-*Last updated: 2026-05-04 — Phase 6 complete (Analyzer Feed)*
+*Last updated: 2026-05-04 — Phase 7 complete (Engagement Overview)*