fix: complete the gallery quality pass — turntable regression, three old-era restages

[TMHSDigital]

Completes the gallery quality pass. Pass two (#62) fixed seven examples but shipped one regression and left three in-scope examples in the old washed style because their verdicts were wrong. This PR fixes exactly those defects and runs the whole-gallery acceptance test that pass two skipped.

Incorrect prior verdicts — flagged for the record

• turntable — pass two's "fix" was itself defective: the still rendered whatever frame the turntable landed on (FRAMES // 4 = ~82° of turn), showing Suzanne face-away where the muzzle and ear read as corrupted geometry. Accepted in review because the reviewer knew what it was; a stranger doesn't.
• gn-sdf-remesh — marked PASS in pass two; actually old-era (light floor, 1100 W key, no view transform, brick-toned red).
• bmesh-gear — marked PASS in pass two ("anatomy reference"); the shipped hero was a flat white gear that did not even match the script's own steel material — the asset predated the current code, and per-image inspection misjudged it as acceptable.

Fixes in this PR (one commit per example)

• turntable — render frame pinned deliberately to frame 4 (~31° of turn: three-quarter view, ears and brow read instantly as Suzanne) with a comment stating why an arbitrary turntable frame is not acceptable; smooth shading made explicit via Mesh.shade_smooth(). House staging kept.
• gn-sdf-remesh — restaged to docs/VISUAL-STYLE.md: spec floor/world values, shaped warm key (650 W), faint cool fill, warm wedge raking the wall, Standard view transform. The crimson now reads saturated instead of brick.
• bmesh-gear — restaged to the spec (floor/world, 700 W warm key, restrained fill, warm wedge, Standard transform). The steel material the script always specified finally shows: bright machined face, dark tooth flanks, warm pool behind.
• depsgraph-export — second-pass improvement: darker slate base cube with a slight sheen (was a large mid-grey slab that dominated the thumbnail), tighter framing. The base-vs-evaluated contrast story now reads at card size.

Reconciled scope — all 14 pre-#61 examples accounted for

Example	Pass two	This pass	Status
swatch-grid	fixed (re-staged, verify-gated)	—	fixed
turntable	"fixed" (regressed)	re-fixed: pinned pose, smooth shading	fixed now
shape-key-blend	fixed (progression)	—	fixed
driver-wave	fixed (reframed + relit)	—	fixed
gn-instance-grid	fixed (relit)	—	fixed
depsgraph-export	fixed (relit)	improved: cube material + framing	fixed now
curve-bevel-arc	fixed (reframed + relit)	—	fixed
gn-sdf-remesh	PASS (incorrect)	restaged to spec	fixed now
bmesh-gear	PASS (incorrect)	restaged to spec	fixed now
wave-displace	PASS	verified in whole-gallery review	genuinely passing — frame-filling saturated sculptural form on near-black
shader-node-group	PASS	verified in whole-gallery review	genuinely passing — dark stage, warm backdrop pool, saturated hero spheres
temp-override-join	PASS	verified in whole-gallery review	genuinely passing — dark stage, warm pool, amber subject
compositor-glare	PASS	verified in whole-gallery review	genuinely passing — neon glow on near-black, the halo is the witness
damped-track-aim	PASS	verified in whole-gallery review	genuinely passing — polished separately in #53, dramatic staging

Phase 3 — whole-gallery acceptance (mandatory, executed)

Gallery regenerated via scripts/build_gallery.py, served locally with python -m http.server from docs/ (the prior run's exit 127 was the server being killed intentionally after use, not a failure to serve), loaded in a real browser at a viewport tall enough to defeat lazy-loading, and scrolled end to end with every thumbnail loaded. Confirmed: no card reads as old-era, no render reads as broken geometry, and the six post-#61 examples still lead.

Verification

Proven by live run (local): check-only exit 0 on Blender 4.5.11 LTS and 5.1.2 for all four touched examples — including both sides of turntable's slotted-actions channelbag shim and its EEVEE engine-id gate (the 4.5 run exercises strip.channelbag, the 5.1 run action_ensure_channelbag_for_slot). All renders on 5.1.2 EEVEE; every candidate inspected at full size, card crop, and thumbnail scale. swatch-grid untouched this pass — its shim coverage stands from #62.

Established by inspection only: --engine cycles render paths and the 4.5 EEVEE-Next render path (identical scene code behind the existing engine-id gates; CI smoke is check-only by design).

No check tolerances touched; no generated pages hand-edited; release-owned version fields untouched. Alt texts verified against the new renders — all four remain accurate (bmesh-gear's alt finally matches its render).

🤖 Generated with Claude Code