coordination: hand off WMO render group materializer

Work-Package: M03-RND-WMO-RENDER-GROUP-MATERIALIZER-001
Agent: sindo-main-codex
Tests: documented in handoff
Fidelity: exact behavior-preserving extraction

coordination/claims/M03-RND-WMO-RENDER-GROUP-MATERIALIZER-001.md

@@ -54,7 +54,28 @@ settings and attachment from the loader into one main-thread materializer.
 
 ## Status
 
-- State: active
-- Done: scope and contracts identified
-- Next: implement and verify materializer delegation
+- State: ready
+- Done: implementation, verification and documentation
+- Next: integrator review and merge
 - Blocked by:
+
+## Handoff
+
+- Commit: `f4d5e29` (`render: extract WMO render group materializer`)
+- Results: materializer PASS `cases=37 iterations=1000 elapsed_ms=2.771`;
+  autonomous headless suite `63/64`, with only the proprietary
+  `verify_adt_m2_placements.gd` probe unavailable because `data/extracted` is
+  absent; cold/editor parse completed without script diagnostics after restoring
+  ignored generated/native worktree artifacts; checkpoint dry-run retained
+  `7/7`; documentation passed with `50` module specifications; coordination
+  passed with `77` historical expired-claim warnings.
+- Fidelity: exact Mesh/MultiMesh identity, indexed/fallback presentation,
+  render settings, attachment and scheduler/queue boundaries are unchanged.
+  No private-asset or original-client visual parity claim is added.
+- Remaining risks: synchronous main-thread Node creation remains; no private WMO
+  visual comparison, long traversal, leak/GPU or p95/p99 evidence.
+- Documentation: new full module specification with API/I/O and data-flow,
+  sequence/dependency diagrams; renderer registry/source map and `RENDER.md`
+  updated.
+
+<!-- OPENWC_HANDOFF:READY:M03-RND-WMO-RENDER-GROUP-MATERIALIZER-001:f4d5e29 -->