run-build

Thin runner for the build stage: assemble locked clips into the final render by running the project's own build script(s). It owns running and recovering, not the engine — the engine lives in the project's scripts, invoked via project.md.

Steps

1. Run the configured command(s). Take commands.build from project.md, substitute {item} with the item's directory, and run it. It typically chains narration → stitch → captions → finalize; run them in the given order. This is the authoritative command — don't guess from prose. If commands.build is missing, stop and ask.
2. On failure, re-run only the failing subcommand, not the whole chain — each stage's output feeds the next, so a captions failure shouldn't force a re-stitch.
3. Respect engine conventions in context.md (clip-native vs. stripped audio, bgm, logo bumper, caption style, word-timing source). context.md overrides on conflict — don't assume; check.
4. Output the final render plus any QA artifact the charter expects (e.g. qa_checklist.md) so the render gate has something to attach. Leave pipeline.md updates to the orchestrator.