render: extract WMO runtime Mesh finalizer

RENDER.md

@@ -1449,6 +1449,22 @@ $exe = Join-Path $env:TEMP 'godot-4.6.1-openwc\Godot_v4.6.1-stable_win64.exe'
 - ADT parsing, quality tasks/results, tile state, cache format versions, material/
   Node/RID finalization, budgets and visible terrain behavior remain loader-owned.
 
+## 2026-07-18 WMO Runtime Mesh Finalizer Extraction
+
+- `WmoRuntimeMeshFinalizer` now owns cached WMO Mesh material refresh version
+  `10`, in-place ArrayMesh surface iteration and WMOBuilder material-definition
+  reconstruction.
+- `StreamingWorldLoader` retains cached-scene traversal, lightweight build-job
+  traversal, Node/MultiMesh attachment, permits and lifetime, and delegates each
+  borrowed Mesh to the service.
+- The historical metadata keys, compact texture0/texture1/texture2 ordering,
+  flags/shader/blend values, cached shader colors and exact Mesh identity are
+  unchanged. Null/unmarked surfaces and null builder results retain their prior
+  Material.
+- Asset-free verification covers `27` identity/version/type/material/source
+  cases and 1,000 current-Mesh calls. This is orchestration extraction, not new
+  build-12340 material or visual parity evidence.
+
 ## Practical Rule For Future Work
 
 If something improves quality but creates visible hitch, it is not done. Move it to bake/cache/background work, split finalization over frames, or prewarm it before the player can see it.