Move the Tier-1 encoder contract out of the stuffed encode.rs facade into a
new encode/codec.rs submodule (plan §7 / W2): EncodedFrame, Codec (all methods
except host_wire_caps), ChromaFormat, EncoderCaps, the Encoder trait,
validate_dimensions, vbv_frames_env, and the dimension + wire-roundtrip contract
tests. host_wire_caps stays in encode.rs alongside the backend-selection probes
it depends on; CodecSupport and its wire-mask test stay too.
encode.rs gains `mod codec;` + `pub(crate) use codec::*;` so every existing
crate::encode::X path — crate::encode::vbv_frames_env, ::Codec, ::Encoder, … —
stays byte-stable. Pure relocation: no call sites touched.
Verified: dev-Mac type-check of both files clean; Linux `cargo check -p
punktfunk-host --features nvenc,vulkan-encode,pyrowave` green (all encode
backends compile against the relocated contract); contract unit tests pass.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
enricobuehler
532b313b8c