93c8dc4712
Turn the 1446-line packet.rs into a packet/ directory module (mod.rs facade + header/packetize/reassemble/tests) behind glob re-exports, so every crate::packet::X path stays byte-stable. Pure move: the header consts + PacketHeader -> header.rs; Packetizer -> packetize.rs; the Reassembler cluster (kept WHOLE -- disjoint-borrow hot path) + loss-window consts -> reassemble.rs; the inline #[cfg(test)] block -> tests.rs. Sole visibility change: LOSS_WINDOW_NS -> pub(super) (a test imports it). No behavior change. Verified on both platforms from a clean HEAD snapshot: Linux clippy (--features quic and --no-default-features, --all-targets -D warnings) + full cargo test; Windows clippy (both feature sets) + cargo test --lib (156 pass). Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>