rnd(M03): extract streaming target planner

Work-Package: M03-RND-STREAMING-PLANNER-001
Agent: sindo-main-codex
Tests: planner/facade/focus/coordinate/manifest/shutdown contracts, seven-checkpoint dry-run, repository gates
Fidelity: preserves wanted/retained radii, boundary prefetch, editor preview, queue priority and cache/render behavior

RENDER.md

@@ -889,6 +889,20 @@ $exe = Join-Path $env:TEMP 'godot-4.6.1-openwc\Godot_v4.6.1-stable_win64.exe'
   visibility, materials or animation. Environment, entity visuals and ground
   query remain explicit follow-up facade contracts in M03.
 
+## 2026-07-15 StreamingTargetPlanner Extraction
+
+- Runtime and editor wanted/retained ADT set calculation now lives in the
+  scene-free `StreamingTargetPlanner`.
+- `StreamingTargetPolicy` preserves existing chunk/tile radii, warm/prewarm/
+  retain margins and the clamped boundary-prefetch threshold.
+- `StreamingTargetPlan` freezes its focus/wanted/retained result; the streamer
+  still owns available paths, load-queue distance sorting, loaded-tile LOD/detail
+  state, async work, caches, nodes and RIDs.
+- Asset-free fixtures cover center, edge/corner prefetch, catalog filtering,
+  clamp and editor behavior plus bounded High-like iteration timing.
+- Cache versions, quality profiles, queue priority and visible rendering rules
+  are unchanged by the extraction.
+
 ## 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.