- `Encoder::encode` returns `Result` (it was `try_encode(..).expect(..)`, panicking on short
planes); tests and the example unwrap explicitly.
- P/B macroblock analysis without a reference codes intra instead of `expect`/`unwrap`;
spatial direct without a list-1 picture predicts zero motion.
- Rate control prior, DPB sliding window, DTS queue, reconstruction buffers, CAVLC writer,
SAD rows and forward 8x8 transforms without `unwrap`/`expect`; skip-macroblock arms in
`write_mb` debug-assert instead of `unreachable!`.
- `#![deny(clippy::unwrap_used, …)]` outside tests.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>