feat(walk): the stride is captured — walking shot 8, traversal check closed

Shot 8 shows the body mid-stride in profile: legs apart, arms counter-swinging. The
traversal release check for 0.2.0 is closed with that evidence.

The reason earlier attempts froze on one pose was not the clip. A probe of the
single-node instance showed the clip advancing normally (assetTime 0.19 -> 1.03,
rate 1.0, playing) while the pawn's speed stayed 0 and the clip stayed Idle: the
call that enables walking sat in the shot sequencer's BeginPlay, which runs before
the player pawn exists, so the cast found nothing and silently did nothing. Moved
into the per-frame follow update, the same run logs walk=1 speed=28 clip=GigLine_Walk
and the stride appears.

Also: the walk expectation was missing from visual_targets.json after the earlier
retirement, so --verify was checking 7 shots while 8 were captured. Restored; 8/8
verify.

Screenshots/README.md

@@ -130,6 +130,21 @@ What it shows: the arms hang down with a soft elbow bend, the hands sit at hip h
 
 ---
 
+## 8. Third-person walk
+
+![Third-person walk: the body mid-stride in profile](demo/review-demo-third-person-walk.png)
+
+- **File:** `demo/review-demo-third-person-walk.png`
+- **View:** tracking camera, 4.2 m to the pawn's right, captured while the pawn walks south under `-walk`
+- **Expected content:** the body mid-stride in profile — legs apart, arms counter-swinging
+- **Verified:** ☑ 2026-11-09 · **Approved:** ☐ pending
+
+**Why it needed new harness:** a fixed camera cannot photograph a pawn moving at 4.5 m/s. Three attempts framed it differently every run and two missed it entirely. The shot actor now has a per-shot `ShotFollow` mode that re-places the camera every frame at a fixed offset in the pawn's frame, and the walk is driven per shot, so the capture is deterministic.
+
+**What it proves:** the walk clip plays and advances. The earlier captures of this shot showed one frozen pose because the sequencer's `BeginPlay` ran before the player pawn existed, so the cast that enables walking silently found nothing and `speed` stayed at zero — the probe read `walk=0 speed=0 clip=Idle` every frame. Moving that call into the per-frame follow update fixed it; the capture now logs `walk=1 speed=28 clip=GigLine_Walk` and shows a stride.
+
+---
+
 ## The iteration loop (uncommitted)
 
 `Tools/visual_loop.py` measures each capture against its reference photograph and turns the deltas into modelling actions for the Blender skill packs: