* craft-video: MPEG-2 and MPEG-1 video decoder from FilmCraft (`mpeg2`)
FilmCraft's crates/mpeg2v at 4bec22bd moves to craft_video::mpeg2 behind the
decoder-only feature `mpeg2`: sources, README and tests (unit, synthetic
streams checked by ffmpeg, the ffmpeg oracle fixtures, hostile sweeps).
Changes in the move: craft-media-testkit instead of filmcraft-testkit, one
test target (tests/mpeg2), crate paths, rustfmt at this repo's width.
New: a memory budget (Decoder::set_memory_budget, craft_video::budget) checked
when a sequence becomes active, and a mutation test over the synthetic
field-picture, 16x8 and dual-prime streams, which ffmpeg's encoder cannot
produce and the hostile sweep therefore never reached.
* craft-video mpeg2: write the restart check without a negated conjunction (clippy nonminimal_bool)