Enforce Remotion-first composition in video-reference-analyst skill

The AGENT_GUIDE establishes Remotion as the preferred composition engine
over FFmpeg, but the reference analyst skill was presenting them as peer
options. This caused the agent to default to FFmpeg during proposals.

- Capability audit template now labels Remotion as "preferred" and FFmpeg
  as "fallback only"
- Added explicit composition engine priority note
- Proposal template separates Composition and Motion as distinct lines

skills/meta/video-reference-analyst.md

@@ -99,10 +99,17 @@ REFERENCE NEEDS          YOUR CAPABILITIES          GAP
 Video clips (sci-fi)     Video gen: 0/12 configured BLOCKED without key
 Narration (deep male)    TTS: ElevenLabs available  READY
 Background music         Music: MusicGen available  READY
-Text animations          Remotion: available        READY
-Fast-cut editing         FFmpeg: available          READY
+Composition engine       Remotion: available        READY (preferred)
+                         FFmpeg: available          READY (fallback only)
 ```
 
+**Composition engine priority:** Always check Remotion availability at this step.
+When Remotion is available, it is the **primary** composition engine — use it for
+transitions, animated text, still-image animation, and scene assembly. FFmpeg is
+the fallback for when Remotion is unavailable, or for simple operations that don't
+benefit from Remotion (pure concat, trim, audio mux). Never default to FFmpeg when
+Remotion is available.
+
 Be honest about gaps. If video generation is needed but unavailable, say so clearly:
 
 ```
@@ -149,7 +156,8 @@ Use this structure for each variant:
 **Visual plan:**
 - Playbook: [closest match + customizations]
 - Visual treatment: [how visuals will be created — which tools, which providers]
-- Motion: [Remotion animations / video gen clips / stock + Ken Burns / etc.]
+- Composition: [Remotion (preferred when available) / FFmpeg (fallback only)]
+- Motion: [video gen clips / Remotion spring animations on stills / etc.]
 
 **Audio plan:**
 - Narration: [yes/no, which TTS provider, voice style]