docs(03-03): complete forest scene plan

- SUMMARY.md with forest scene implementation details
- STATE.md updated with progress and decisions
- ROADMAP.md updated with plan progress
- Requirements FRST-01, FRST-02, FRST-03 marked complete

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

.planning/STATE.md

@@ -2,15 +2,15 @@
 gsd_state_version: 1.0
 milestone: v1.0
 milestone_name: milestone
-status: verifying
-stopped_at: Phase 3 context gathered (assumptions mode)
-last_updated: "2026-03-29T11:28:24.608Z"
+status: executing
+stopped_at: Completed 03-03-PLAN.md
+last_updated: "2026-03-29T11:42:33.082Z"
 last_activity: 2026-03-29
 progress:
   total_phases: 4
   completed_phases: 2
-  total_plans: 10
-  completed_plans: 10
+  total_plans: 15
+  completed_plans: 11
   percent: 0
 ---
 
@@ -21,13 +21,13 @@ progress:
 See: .planning/PROJECT.md (updated 2026-03-29)
 
 **Core value:** Das Kind übt freiwillig weiter, weil es wissen will, was als Nächstes im Wald erscheint — nicht weil es Punkte sammelt.
-**Current focus:** Phase 02 — gemini-integration-asset-pipeline
+**Current focus:** Phase 03 — komplettes-spielerlebnis
 
 ## Current Position
 
-Phase: 3
-Plan: Not started
-Status: Phase complete — ready for verification
+Phase: 03 (komplettes-spielerlebnis) — EXECUTING
+Plan: 2 of 5
+Status: Ready to execute
 Last activity: 2026-03-29
 
 Progress: [░░░░░░░░░░] 0%
@@ -62,6 +62,7 @@ Progress: [░░░░░░░░░░] 0%
 | Phase 02 P04 | 1min | 1 tasks | 2 files |
 | Phase 02 P03 | 6min | 2 tasks | 12 files |
 | Phase 02 P05 | 3min | 3 tasks | 7 files |
+| Phase 03 P03 | 2min | 2 tasks | 3 files |
 
 ## Accumulated Context
 
@@ -88,6 +89,7 @@ Recent decisions affecting current work:
 - [Phase 02]: Fixed imageModel name: gemini-3.1-flash-preview-image -> gemini-3.1-flash-image-preview (was 404)
 - [Phase 02]: Asset generation script skips existing files for idempotent re-runs
 - [Phase 02]: Vite static imports for avatar PNGs with onerror emoji fallback pattern
+- [Phase 03]: Object URLs tracked in module-level array and revoked on re-render to prevent memory leaks
 
 ### Pending Todos
 
@@ -99,6 +101,6 @@ None yet.
 
 ## Session Continuity
 
-Last session: 2026-03-29T11:28:24.601Z
-Stopped at: Phase 3 context gathered (assumptions mode)
-Resume file: .planning/phases/03-komplettes-spielerlebnis/03-CONTEXT.md
+Last session: 2026-03-29T11:42:33.074Z
+Stopped at: Completed 03-03-PLAN.md
+Resume file: None