Teardown leak: _free_pipeline_vram now records the pipeline's CUDA
storage pointers up front and, after the normal teardown+gc, walks
gc.get_objects() and nulls any surviving tensors out of their list/dict
referrers (the proven pass from the CUDA text backend's cleanup) — the
"~22 GB untracked (teardown leak; referenced elsewhere)" VRAM is now
reclaimed instead of poisoning every later load until a restart. Names
the holders when it fires so future leak sources identify themselves.

Tracking: a video pipeline only registers in manager.models AFTER its
multi-minute load, so concurrent loads raced the free-VRAM check into
mutual OOM. note_loading()/clear_loading() reserve the model's estimate
for the whole load window; _get_free_vram_gb subtracts reservations and
the orphan-VRAM check counts them (no more false "teardown leak" for an
in-progress load). The embeddings OOM-retry waits out active
reservations (bounded 300s) before evicting and retrying.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_014S8VtAvG499SsCbeESRK7V