fix(M03): support cold rendered ground sample startup

docs/modules/world-renderer.md

@@ -293,6 +293,8 @@ Exact exported settings and cache versions remain documented in [`../../RENDER.m
   gameplay or EditorPlugin package code.
 - Ground-query facade contract: available/unavailable typed result delegation,
   detached nested diagnostics and terrain-probe source migration without private access.
+- Rendered-ground value contract: available/non-finite/unavailable invariants pass
+  from a cold Godot class cache before editor import.
 - Integration/E2E: Eastern Kingdoms/Kalimdor streaming scenes, seven M00
   cold/warm checkpoints and one dedicated mapped server-spawn checkpoint.
 - Fidelity evidence: семь локальных build 12340 reference JPG покрывают terrain/ADT/M2/WMO/liquid/sky и реальный `GryphonRoost01`; automated cold/warm metrics имеют `compared=14`, `missing=0`. Sky использует приблизительно paired camera, а animated-M2 остаётся asset-paired/placement-unpaired из-за synthetic probe.
@@ -361,6 +363,7 @@ Exact exported settings and cache versions remain documented in [`../../RENDER.m
 | `src/domain/streaming/streaming_focus.gd` | Immutable camera-independent streaming position contract |
 | `src/tools/verify_streaming_focus.gd` | Headless contract, dependency and runtime/tool wiring regression |
 | `src/tools/verify_world_render_facade.gd` | Focus/metrics/ground delegation, snapshot isolation and consumer wiring regression |
+| `src/tools/verify_rendered_ground_sample.gd` | Cold-start renderer ground result invariant regression |
 | `src/tools/verify_streaming_target_planner.gd` | Planner behavior, dependency and bounded timing regression |
 | `src/tools/verify_render_budget_scheduler.gd` | Scheduler bounds, shared-lane priority, cancellation and timing regression |
 | `src/tools/verify_renderer_internal_access.gd` | Gameplay/EditorPlugin/registered renderer-tool boundary gate derived from private streamer fields |