Add web/js/workspace/local-video.mjs: ISO-BMFF (MP4/MOV/M4V) and Matroska
(MKV/WebM) walkers that read only the container tags the server asks ffprobe
for, slicing box and element headers, carrier names and retained values within
the server's budgets and never a byte inside mdat or a Cluster; a port of
utils/video_metadata.select_video_carrier with the record budgets of
read_inspection_file; and a byte-exact json.loads/json.dumps round trip so
envelope objects reserialize as the server spells them.
Every naming rule mirrors ffprobe 9.0.2 on hand-built files: legacy ilst atoms,
mdta keys, joined repeats, data types, Matroska language and default handling,
and Tags behind a Cluster found only through a SeekHead.
Tests: node units over byte-exact container builders and the committed
fixtures; a Python parity test comparing the local carrier with the server's
selection from the same tag maps (mocked probe) and from the same files (real
ffprobe, including 1 MiB + 2.5 MiB per-key records); an ffprobe
characterization of the recorded fixture maps.
Vito Sansevero
2133f715e7