* craft-video: AV1 decoder from FilmCraft (`av1-decode` feature)
FilmCraft's crates/av1 at 4c0d2ad7 becomes craft_video::av1::decode. The encoder moves to
av1/encode and is still exported from craft_video::av1. Feature av1 now turns on av1-decode and
av1-encode, so either half can be built without the other.
The ignored speed tests no longer read the thread CPU clock (FilmCraft used rustix for it).
craft_video::budget (the picture memory budget from DeckCraft's bitstream crate) is added for the
next commit. craft-video is built at opt-level 3 in the dev profile, as FilmCraft built its
codecs.
* craft-video: AV1 decoder hardening from DeckCraft's copy
- The picture store (eight reference slots, the new frame, frames in flight) is checked against
a memory budget before a frame is allocated; Decoder::set_memory_budget.
- Non-uniform tile spacing is refused past MAX_TILE_COLS columns or MAX_TILE_ROWS rows.
* craft-video: AV1 fuzz seeds are 64x64 so SVT-AV1 2.x can encode them
FilmCraft's seeds were 64x48; the SVT-AV1 2.3 on the Ubuntu runners refuses a source under 64
lines, and an encoder that exists but fails is a test failure, not a skip.
