hyperframes: add HTML/CSS/GSAP as a parallel composition runtime

Separates creative grammar (renderer_family) from technical engine
(render_runtime) so HyperFrames can stand alongside Remotion as a
first-class runtime instead of masquerading as a Remotion sub-case.
Locks runtime choice at proposal stage and enforces it end-to-end: the
schemas require it, video_compose routes by it, the reviewer fails
closed on silent swaps, and a parametrized contract test walks every
pipeline manifest to ensure each planning-stage skill explains the
conversation to the user. Adds hyperframes_compose (scaffold/lint/
validate/render/doctor/add_block), a playbook -> CSS style bridge, and
vendored HyperFrames Layer 3 skills from commit d291358, pinned via
PROVENANCE.md for future re-sync. Final_review now records
render_runtime_used and runtime_swap_detected so compose lies are
catchable after the fact.

skills/pipelines/talking-head/compose-director.md

@@ -4,6 +4,14 @@
 
 You have edit decisions and an asset manifest. Your job is to render the final talking-head video: apply the enhancement chain, burn subtitles, mix audio, and encode to the target profile.
 
+## Runtime Routing (HARD CONSTRAINT — Remotion or FFmpeg only)
+
+Phase 1 deferred from HyperFrames. `edit_decisions.render_runtime` must be `"remotion"` (preferred — uses the `TalkingHead` composition + `remotion_caption_burn`) or `"ffmpeg"` (for source-footage concat with no composition).
+
+- If `edit_decisions.render_runtime == "hyperframes"`, stop. Re-open the idea stage and surface the constraint. Silent rewrite is a governance violation.
+- Per AGENT_GUIDE.md → "Present Both Composition Runtimes (HARD RULE)": the pipeline's constraint doesn't skip the conversation. Present the constraint to the user so they know HyperFrames exists but isn't viable here. Record a `render_runtime_selection` decision with hyperframes `rejected_because: "TalkingHead + caption parity deferred on talking-head"`.
+- Pass `proposal_packet`/`brief` to `video_compose.execute()` for runtime-swap detection.
+
 ## Prerequisites
 
 | Layer | Resource | Purpose |

skills/pipelines/talking-head/idea-director.md

@@ -6,6 +6,12 @@ You are starting a talking-head video project. You have raw footage of a person
 
 Unlike the explainer pipeline (which starts from a topic), you start from existing footage. The brief documents what you're working with and what the final video should look like.
 
+## Runtime Selection (MANDATORY — present the constraint, don't silently pick)
+
+Lock `render_runtime = "remotion"` (preferred — uses `TalkingHead` + `remotion_caption_burn`) or `"ffmpeg"` (for source-footage concat with no composition). **HyperFrames is NOT a valid runtime on this pipeline in Phase 1** — the TalkingHead composition and word-level caption burn have no HyperFrames parity yet.
+
+Per AGENT_GUIDE.md → "Present Both Composition Runtimes (HARD RULE)": do NOT silently default to remotion. Tell the user: "HyperFrames is available, but talking-head depends on the Remotion TalkingHead composition, so remotion is the only viable composition choice (or ffmpeg for a raw cut) — OK to proceed?" Record a `render_runtime_selection` decision with hyperframes as a rejected option (`rejected_because: "TalkingHead + caption parity deferred on talking-head"`).
+
 ## Prerequisites
 
 | Layer | Resource | Purpose |