feat(cli): info --media lists every clip the render hears, on the film's clock - #7235

What

hyperframes info --media --json adds heard: every clip the render mixes into the film, scenes included, on the film's clock. Each entry has src, start, end, mediaStart, playbackRate, volume and type. Text mode prints one "Heard" line per clip. Without --media, info is unchanged.

Why

A tool that needs to know which clips the viewer hears (captions, for one) had to walk the HTML itself, and a second walker drifts from the render. Two shapes it got wrong:

• a speaking clip inside a timed wrapper in a scene;
• a speaking clip with no data-duration, which runs until its media ends.

The render already knows the answer. This exposes it from the CLI, so callers read the same list the mix uses instead of rebuilding it.

How

heardClips(projectDir) in utils/projectMedia.ts (the file check already uses to load the producer) bundles the project with core's bundleToSingleHtml (scenes inlined, nested src rebased) and runs the producer's collectRenderMedia over it: the same parser the render uses, so the same rule for what is audible (<audio>, and a <video data-has-audio="true"> that is not muted) and the same clock.

The collector ends an unbounded clip at its scene's end. The mix stops earlier if the media runs out, so each clip's end becomes min(end, start + (mediaSeconds - mediaStart) / rate), with the length probed by the engine's extractAudioMetadata. A clip whose media start is past its file's end is left out. Each file is probed once. A looping clip, a ramped rate or a file that cannot be probed keeps the collector's end.

Test plan

• Unit tests added/updated: projectMedia.test.ts, four tests on a real bundled project with a fixed probe:
  • "hears a speaking video inside a timed wrapper in a scene, where the render plays it": a wrapper at 1 s in a scene at 10 s, the clip is heard 10 s to 15 s.
  • fails without the fix: projectMedia.test.ts "ends a speaking clip with no set length where its media runs out, not where its scene ends": 12 s to 17 s, not to the scene's end at 30 s. It fails with the probe cap removed.
  • "hears a video only when it says data-has-audio and is not muted, as the render does".
  • fails without the fix: projectMedia.test.ts "leaves out a clip that starts past its media's end, and reads each file's length once": a clip whose media start is past its file's end adds nothing to the mix, so it is not listed, and two clips of one file probe it once. It fails with either change taken out.
  • info.test.ts passes media: false in its args. The touched files' tests (17) pass three runs in a row.
• Manual testing performed: the built CLI on a project with a real mp4 (sine audio) in both shapes. info --media --json prints only JSON, with heard holding the clip at 10 s to 15 s and the one at 22 s to 27 s; info --json has no heard key; text mode prints both "Heard" lines.
• Documentation updated (if applicable): the info section of docs/packages/cli.mdx.
• Comments follow CONTRIBUTING.md "Comments": one doc line on HeardClip and one on heardClips.

Size

About 55 lines of source in two files, about 85 of tests and three doc lines. One change: info can print the render's audible clips.