Slice 5a, scaffolding only. 607 green.
- `Source.IsReplayLayer` + schema column + roundtrip: a media layer that shows saved clips instead of a
chosen file. The compositor needs to know nothing — it is a media layer whose path the VM owns.
- **Two spec corrections from the creator (2026-11-10), recorded in the task:**
1. The immediate replay of a fresh clip happens **only in the Live scene**. While it plays, **F10 is
inert** ("replay in progress").
2. That guard replaces the "layer excluded from its own clip" idea, which is **impossible** with one
encoder and two muxes: the clip is a second mux of the same frames, so it necessarily contains what
viewers saw. No second encode, no fiction about a clean feed.
Remaining for 65: the add-layer menu entry, `ClipSaved` → play (Live: once then hide; elsewhere: loop the
kept set), `SessionCompleted` → advance or hide, and silent-by-default audio.
gramps
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