//! Pure Rust sans-io software codec fallbacks (no C codec FFI).
//!
//! No C codec FFI (`OpenH264`, `libvpx`, …). Codec logic lives in Rust cores
//! (or reviewed Rust deps such as `rav1e`) behind sans-io adapters. Stage 5 of the
//! workspace roadmap; see `docs/roadmap.md` for this crate's own staging.
//!
//! Current scope: [`h264`] Annex-B/AVCC NAL unit framing, SPS/PPS header parsing, and a
//! Baseline/CAVLC/I-slice single-frame pixel decode loop (`I_16x16`/`I_PCM` macroblocks
//! only, no deblocking filter); [`pcm`] raw PCM passthrough encode/decode; [`av1`] AV1
//! encode via `rav1e`. See `adr/0001-h264-baseline-decoder-first.md` for the H.264 decode
//! staging plan, `adr/0003-cavlc-i-slice-first-decode.md` for this decode loop's exact
//! scope cuts, and `adr/0002-rav1e-av1-encode.md` for the AV1 adapter scope.
// ── merged platform/domain modules (ADR-0021) ──