docs(state): record phase 1 context session

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

.planning/STATE.md

@@ -1,3 +1,19 @@
+---
+gsd_state_version: 1.0
+milestone: v1.0
+milestone_name: milestone
+status: planning
+stopped_at: Phase 1 context gathered
+last_updated: "2026-04-10T08:56:16.637Z"
+last_activity: 2026-04-10 — Roadmap created, 5 phases derived from 27 requirements
+progress:
+  total_phases: 5
+  completed_phases: 0
+  total_plans: 0
+  completed_plans: 0
+  percent: 0
+---
+
 # Project State
 
 ## Project Reference
@@ -56,6 +72,6 @@ None yet.
 
 ## Session Continuity
 
-Last session: 2026-04-10
+Last session: 2026-04-10T08:56:16.634Z
-Stopped at: Roadmap created — ready to plan Phase 1
+Stopped at: Phase 1 context gathered
-Resume file: None
+Resume file: .planning/phases/01-foundation/01-CONTEXT.md