docs(state): record phase 5 context session

.planning/STATE.md

@@ -2,16 +2,16 @@
 gsd_state_version: 1.0
 milestone: v1.0
 milestone_name: milestone
-status: executing
-stopped_at: Completed 04-07-PLAN.md
-last_updated: "2026-06-09T18:23:42Z"
-last_activity: 2026-06-09 -- Phase 04 plan 07 complete (gap-closure: LIST-03 + T-04-08)
+status: completed
+stopped_at: Phase 5 context gathered
+last_updated: "2026-06-09T19:13:07.387Z"
+last_activity: "2026-06-09 -- Phase 04 plan 07 complete (gap-closure: LIST-03 + T-04-08)"
 progress:
   total_phases: 15
   completed_phases: 4
   total_plans: 28
   completed_plans: 28
-  percent: 100
+  percent: 27
 ---
 
 # Project State
@@ -140,6 +140,6 @@ Recent decisions affecting current work:
 
 ## Session Continuity
 
-Last session: 2026-06-09T18:23:42Z
-Stopped at: Completed 04-07-PLAN.md (Phase 04 fully complete)
-Resume file: None
+Last session: 2026-06-09T19:13:07.379Z
+Stopped at: Phase 5 context gathered
+Resume file: .planning/phases/05-web-push-notifications/05-CONTEXT.md