fix(audit): converge on the 2026-07-23 animation standard — tool sync, QuatSkin INBOX, registry corrections

From the conformance audit (ariki-game .agents/audits/animation-standard-assessment-2026-07-23.md):
- tools/: cc_retarget + mixamo_retarget re-synced from ariki-game (were stale forks
  missing --despike/--fingers/--map ual); kevin_retarget path now repo-relative;
  mirror rule documented in exchange/GUIDE.md
- INBOX/lena: add canonical Ariki_Female_QuatSkin.glb; README marks MixamoSkin superseded
- REGISTRY: tide_dance_01 flagged (no DanceType enum entry); rain_dance note corrected
  (RainDance IS in the enum); boat table notes live canoedismount1/run_to_dive; QC split
  (loop_qc pre-commit vs anim_qc post-ingest) documented
- docs/iclone-bridge.md: stub created (GUIDE referenced it but it never existed)

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

docs/iclone-bridge.md

@@ -0,0 +1,18 @@
+# iClone bridge — PC-lane overview
+
+(Stub created 2026-07-23 — this path was referenced by `exchange/GUIDE.md` but never
+written. The full operational detail lives elsewhere; this page just routes you.)
+
+The Mac↔PC animation bridge: iClone 8 + Video Mocap on Jeremy's Windows machine authors
+motion; this repo carries files both directions; ariki-game consumes 65-bone Quaternius
+GLBs.
+
+| Need | Go to |
+|---|---|
+| Which exchange/ folder to use, when files move/archive | `exchange/GUIDE.md` |
+| Naming (nd_## → ceremony codes), loop-pair rule, registry | `docs/dances/REGISTRY.md` |
+| Filming rules, iClone/AccuFACE settings, mocap cleanup, FBX export | `iclone-video-mocap` skill (`.claude/skills/` here and in ariki-game) |
+| CC FBX → Quaternius GLB conversion | `tools/cc_retarget.py` (mirror of ariki-game — game copy is authoritative) |
+| Looping (`_pp`) + QC gates | `tools/pingpong_bake.py` + `tools/loop_qc.py`; game-side `anim_qc.py` (split documented in REGISTRY.md) |
+| Game-side landing zone | `ariki-game/assets/quaternius/dancegen/` + `assets/dances/*.json` |
+| The skeleton/pack standard itself | `ariki-game/.humans/animation-bone-sources.html` + `.agents/wiki/quaternius-ual-packs.md` |