v0.6.6

Published to crates.io as mfsk-core v0.6.6.

Release notes are auto-generated from merged PRs; see the crate's
CHANGELOG.md
for curated release notes.

Prebuilt mfsk-ffi-ft8 binaries (FT8 C ABI) are attached
below for users who want to drop the decoder into a non-Rust
project without setting up the cross-toolchain themselves —
see docs/EMBEDDED.md
for the integration guide.

What's Changed

• fix(qso): slot-parity-aware TX gating to prevent peer collision on decode spill by @jl1nie in #112
• docs+rustdoc: square up LlrT narrative + drain other frozen-mid-narrative claims by @jl1nie in #111
• ci: skip Build/Test/C++ matrix on docs-only PRs (#113) by @jl1nie in #114
• docs: cleanup stale archives + move CLEANUP_2026_05 to historical/ by @jl1nie in #115
• feat(ft8): auto-AP iaptype-2 from same-slot decoded callsigns (#117) by @jl1nie in #118
• refactor: retire DecodeDepth::Bp + EqMode::Adaptive (#73, #74) by @jl1nie in #119
• cleanup(ft4/fst4): drop unused DecodeStrictness param (#72) by @jl1nie in #120
• ci(release): pass GITHUB_TOKEN to xtensa-toolchain action to dodge 403 race by @jl1nie in #109
• feat(s3-app): BtnA long-press demo mode in BootMode::Qso by @jl1nie in #121
• chore: directory cleanup + gitignore gaps by @jl1nie in #122
• feat(embedded): Phase C — speculative pass2+stage3 during audio tail by @jl1nie in #123
• fix(s3-app): button GPIO swap + menu overlay survives WF repaints by @jl1nie in #124
• perf(embedded): Phase D1 aes3 FFT + D2' Goertzel hot-path; fix menu overlay render order by @jl1nie in #127
• perf(ft8): D3 allsum sliding window + m-outer loop order by @jl1nie in #130
• perf(ft8): D4 demux-mag² DC-hoist + 4× unroll; migrate rx_wavsim to run_speculative_slot by @jl1nie in #131
• feat(cores3): Phase 0-Core crate skeleton for M5Stack CoreS3 by @jl1nie in #132
• feat(ft8): coarse_sync top-5 DT median as cold-start bootstrap by @jl1nie in #133
• chore(release): 0.6.6 — cold-start slot bootstrap by @jl1nie in #134

Full Changelog: v0.6.5...v0.6.6