feat(media): graduate used experience media into git via LFS (coast_birdrock transcoded)

The curated clip bases, per-scale audio, and 154 baked altitude morphs are the
actual experience content, so they're committed via git-LFS (self-hosted Gitea
LFS store). coast_birdrock/base.mp4 was re-encoded 68MB->22MB (25Mbps->8Mbps,
1080p30 unchanged) to fit the git.benstull.org front-end nginx upload limit; its
16 morphs were re-baked. Stale right_variants stay gitignored. Adds .gitattributes
(LFS) and negates the used media back into git in .gitignore. Also records the
LFS media-graduation decision in the plan doc.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

docs/superpowers/plans/2026-06-27-altitude-clip-pair-morph-lock.md

@@ -925,7 +925,15 @@ git commit -m "chore(media): regenerate 154 clip-pair morphs + manifest"
 
 **Type consistency:** `Transition(from_clip, to_clip, file, model)` (T3) used by `morph_for` (T3), `load_ring` (T3), `resolve_move` (T4), `resolved_move_to_dict` (T6). `MorphStep`/`ResolvedMove` fields (T4) match the serializer (T6) and the renderer's `step.{from_clip,to_clip,file,to_index,blended}` + `move.target_clip_id` (T7). `morphByPair` key `"from→to"` consistent in build (T7 S1) and lookup (T7 S4).
 
-**Open items (resolved at the review gate by the operator):**
-1. **Storage/repo weight:** ✅ Commit the 154 short mp4s into `sample_media` (extends the existing precedent of committing the 5 + bases).
-2. **`build_pool_manifest.py` CLI:** ✅ Approach approved; confirm the actual entrypoint flag during execution (Task 9 Step 1).
-3. **Zoom-out E2E:** ✅ Added — Task 8 now covers zoom-in + lock **and** a zoom-out (`.rev` morph) + lock case.
+**Open items (resolved at the review gate + during execution):**
+1. **Storage/repo weight:** Corrected during execution — `sample_media` was entirely
+   gitignored (regenerated from the builder), NOT already committed as the plan first
+   assumed. Operator decision: the media that has **graduated** into the actual
+   experience (curated clip bases, per-scale audio, the 154 morphs — ~526 MB) is now
+   committed via **git-LFS**, pointing at the self-hosted Gitea LFS store
+   (`git.benstull.org`). Stale/unused media (parked `right_variants`, ~1.6 GB) stays
+   gitignored (not deleted from disk — that's a separate explicit cleanup).
+2. **`build_pool_manifest.py` CLI:** ✅ `python simulator/build_pool_manifest.py --media`
+   rebuilds the manifest + bakes all morphs (confirmed at execution).
+3. **Zoom-out E2E:** ✅ Task 8 covers zoom-in + lock **and** zoom-out (`.rev` morph) + lock.
+   Note: one wheel notch = 60 deltaY = one detent (`Math.trunc(deltaY/60)`).