Adds per-entity part-transform side-table mirroring _rotationByEntity.
SpawnFromHook now transforms the hook offset through partTransforms[partIndex]
before rotating to world space. Backwards-compatible: entities without
registered part transforms fall through to identity (pre-C.1.5b behavior),
so the existing C.1.5a rotation-seed test stays green.
Adds SetEntityPartTransforms public method. Cleared on StopAllForEntity
alongside the rotation entry.
2 new xUnit tests:
- SpawnFromHook_AppliesPartTransform_WhenRegistered — part 1 lifted +Z=1,
hook offset (1,0,0), PartIndex=1 → world (1,0,1).
- SpawnFromHook_FallsBackToIdentity_WhenPartIndexOutOfBounds — PartIndex=99
on a 2-part array → offset applied without crash, pre-C.1.5b behavior.
Closes the renderer side of #56. EntityScriptActivator wiring (Task 3)
lands next.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>