refactor(M03): extract M2 runtime rebuild classifier

RENDER.md

@@ -35,6 +35,7 @@ Paired run 2026-07-11 подтвердил крупный coordinate/placement g
 - `src/render/wmo/wmo_scene_resource_cache_state.gd` - validated cached-WMO PackedScenes, negative cache and pending `.tscn` paths without file/I/O/Node ownership.
 - `src/render/liquid/adt_water_load_pipeline_state.gd` - ADT water pending FIFO/dedupe, active task IDs and worker-safe parsed-result mailbox without parser or Node ownership.
 - `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/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.
@@ -1039,6 +1040,22 @@ $exe = Join-Path $env:TEMP 'godot-4.6.1-openwc\Godot_v4.6.1-stable_win64.exe'
 - Cache formats, quality profiles, batching output and visible rules are unchanged.
   Asset-backed p95/p99 and spatial-cell batching evidence remain pending.
 
+## 2026-07-17 M2 Runtime Mesh Rebuild Classifier Extraction
+
+- `M2RuntimeMeshRebuildClassifier` now owns the memoized decision used when a
+  stale cached M2 mesh may need an in-memory rebuild from raw data.
+- Existing triggers are unchanged: any billboard flag/positive billboard vertex
+  count, or a referenced non-identity UV rotation/absolute rotation speed above
+  `0.000001` across at most four texture stages.
+- Invalid batch variants and combo/transform indices remain skipped. The first
+  decision for a normalized path remains cached until the same two historical
+  map/shutdown clear sites.
+- `StreamingWorldLoader` still loads raw M2 data, checks
+  `M2_MATERIAL_REFRESH_VERSION`, calls `M2Builder`, adopts/falls back to Meshes
+  and owns ResourceLoader/finalization budgets.
+- No cache version, shader, material, geometry or visible rule changed. Synthetic
+  predicate timing is not asset-backed descriptor-pressure/p95/p99 evidence.
+
 ## 2026-07-17 WMO Placement Resolver Extraction
 
 - `WmoPlacementResolver` now owns lowercase/slash cache-key normalization,