refactor(M03): extract M2 mesh resource cache state

Work-Package: M03-RND-M2-MESH-RESOURCE-CACHE-001
Agent: sindo-main-codex
Tests: 35 headless renderer/coordinate contracts pass; checkpoint dry-run 7/7; documentation and coordination gates pass
Fidelity: preserves exact Mesh references, replacement semantics and final-shutdown lifetime; no visual parity claim

RENDER.md

@@ -37,6 +37,7 @@ Paired run 2026-07-11 подтвердил крупный coordinate/placement g
 - `src/render/liquid/adt_water_scene_finalizer.gd` - stateless main-thread ADT water build/attach and optional persisted Editor ownership through the existing ADTBuilder.
 - `src/render/m2/m2_runtime_mesh_rebuild_classifier.gd` - memoized billboard/UV-rotation decision for stale cached M2 runtime mesh refresh.
 - `src/render/m2/m2_mesh_load_pipeline_state.gd` - static M2 threaded-load request records, terminal statuses and completion-order finalize FIFO without I/O or Mesh ownership.
+- `src/render/m2/m2_mesh_resource_cache_state.gd` - normalized-path prepared static M2 Mesh references with final-shutdown lifetime.
 - `src/scenes/streaming/eastern_kingdoms_streaming.tscn` - текущая сцена для проверки Azeroth/Eastern Kingdoms.
 - `addons/mpq_extractor/loaders/adt_builder.gd` - сборка ADT terrain, control splat материалов и MH2O liquids.
 - `addons/mpq_extractor/loaders/m2_builder.gd` - сборка статического M2 mesh/material.
@@ -1073,6 +1074,19 @@ $exe = Join-Path $env:TEMP 'godot-4.6.1-openwc\Godot_v4.6.1-stable_win64.exe'
 - Cache formats, material refresh, profiles and visible output are unchanged.
   Synthetic state timing is not asset-backed I/O, leak or p95/p99 evidence.
 
+## 2026-07-17 M2 Mesh Resource Cache State Extraction
+
+- `M2MeshResourceCacheState` now owns normalized-path references to prepared
+  static M2 Mesh resources. Lookup returns the exact retained reference and a
+  later store for one path keeps the historical replacement behavior.
+- The cache retains map-refresh lifetime and clears only at the existing final
+  runtime-cache shutdown site after asynchronous work is drained.
+- `StreamingWorldLoader` still owns normalization, `.tscn`/`.glb` selection,
+  ResourceLoader I/O, Mesh extraction, material refresh/rebuild, shared missing
+  and prototype/animated caches, permits and MultiMesh materialization.
+- Cache formats, refresh metadata, profiles and visible output are unchanged.
+  Synthetic cache timing is not asset-backed memory/leak or p95/p99 evidence.
+
 ## 2026-07-17 WMO Placement Resolver Extraction
 
 - `WmoPlacementResolver` now owns lowercase/slash cache-key normalization,