feat(cog-pose): --adapter CLI flag for per-room calibration

Completes the end-to-end product path: cog-pose-estimation run --config
<cfg> --adapter <room.safetensors> loads the shared base + a per-room LoRA
adapter for calibrated inference. Adds InferenceEngine::with_adapter()
(default weights + adapter) and logs when a calibration adapter is active.
6/6 tests pass.

Co-Authored-By: claude-flow <ruv@ruv.net>