feat(motion,runtime): wire the three craft capabilities to the video-authoring dev (#544)

Playwright, the taste-skill design bar, and hyperframes were all
implemented — and each stopped one hop short of the hands doing video
work: playwright reached only fe-qa/ux-qa, the design bar's web-UI dials
actively pointed a video task at 'dense product UI -> motion 2-3', and
hyperframes' agent-facing doctrine never reached any agent. Three wires:

- vendor the official HyperFrames agent skills (hyperframes-core,
  -keyframes, -creative) under motion/skills/ at a pinned upstream
  commit (Apache-2.0, attribution headers; prose reflowed to house
  style, re-vendor note in each header); README and the dev video
  prompt block point at them
- register the playwright MCP for a ux-dev spawned onto a source=video
  task (_is_video_authoring_spawn: fail-closed role/team/task-source
  probe) so the composition author can watch their HTML live in a real
  browser between renders — gating-only, agent-ux already bakes the
  browser; QA gating unchanged, be-qa/ordinary ux-dev still excluded
- design bar video-mode override in the ux_ui team prompt: video tasks
  are films, the web dials do not apply — use the cinematography bar
  and the vendored doctrine instead

Co-authored-by: Renn F <rennf93@users.noreply.github.com>

agents/prompts/teams/ux_ui.md

@@ -42,6 +42,7 @@ State your read in your `decision` note before you build — don't silently defa
 - **MOTION_INTENSITY (1-10):** 1-3 static (hover/active only) · 4-7 fluid `transform`/`opacity` transitions · 8-10 scroll-driven choreography. Above 3, `prefers-reduced-motion` support is mandatory.
 - **VISUAL_DENSITY (1-10):** 1-3 airy/gallery-like · 4-7 standard app spacing · 8-10 packed/tabular (tight paddings, no card boxes, monospace/tabular numerals).
 - **Defaults:** dense product UI (admin panels, dashboards, data tables) → `2-3 / 2-3 / 7-8`. Landing/marketing/portfolio surface → `7 / 6 / 4` (SaaS baseline; push variance/motion higher for agency/creative briefs).
+- **Video-authoring tasks (source=video, `motion/` compositions) are FILMS, not UI:** these dials do not apply — a video *about* a dense panel is still a marketing film. Use `motion/README.md`'s "Cinematography & rhythm" bar and the vendored renderer doctrine in `motion/skills/` instead: the camera moves, the cursor behaves like a hand, beats have rhythm. Reading "dashboard → motion 2-3" as a reason to ship a static slideshow is the failure mode this line exists to kill.
 
 ### Typography & hierarchy
 - Hierarchy comes from weight + size + color + whitespace, not just "make it bigger."