chore: release v0.5.1

[MagicalTux]

🤖 New release

• compcol: 0.5.0 -> 0.5.1 (✓ API compatible changes)

Changelog

0.5.1 - 2026-05-30

Other

• StuffIt 5 Arsenic (method 15) decoder, validated against real archives (#73)
• real StuffIt method-13 (LZ+Huffman) decoder, validated against real archives (#72)
• StuffIt classic method-5 (LZAH) decoder, validated against real archives (#71)
• decode the raw method payload (no invented length prefix) (#70)
• (release-plz) create the GitHub Release with RELEASE_PLZ_TOKEN (#63)
• Add LHA, BCJ/Delta filters, ARC Crunch/Squeeze, and StuffIt-13 building blocks (#68)

Added

• StuffIt 5 Arsenic codec (arsenic, compression method 15): BWT-based —
  a carry-less range/arithmetic decoder (9 adaptive models) → selector-driven
  un-MTF/un-RLE → inverse BWT → optional de-randomization → final RLE →
  CRC-32. Decode-only, self-terminating (in-band end-of-blocks + CRC trailer).
  Clean-room from a facts-only spec, with the fixed interop tables (9 model
  parameters + 256-entry randomization table) supplied as a separately-licensed
  adjunct. Validated bit-exactly against real StuffIt 5 archives — 46 method-15
  forks across 5 fixtures verify (in-stream CRC-32 + declared size), and all 11
  data forks SHA-256 match the reference unar output.

• StuffIt classic LZAH codec (lzah, compression method 5): LZSS sliding
  window (4 KiB, MSB-first) + a single 314-symbol adaptive Huffman tree,
  decode-only. Clean-room from a facts-only functional spec; the raw fork
  payload is decoded with the uncompressed size supplied out of band via
  DecoderConfig::with_len (StuffIt has no in-band end marker). Validated
  bit-exactly against real classic SIT! archives — 17 method-5 forks across
  5 fixtures pass the stored per-fork CRC-16.

• LHA / LZH codecs (lha): -lh1- (adaptive Huffman) and
  -lh4-/-lh5-/-lh6-/-lh7- (static Huffman) LZSS methods, encoder + decoder.
  Clean-room from Okumura's public-domain LZHUF / ar002 descriptions.

• BCJ branch-converter filters (bcj): reversible x86, ARM, ARM-Thumb,
  ARM64, PowerPC, SPARC, IA-64, and RISC-V filters (public-domain LZMA SDK
  lineage), encoder + decoder.

• Delta filter (delta): reversible byte-wise delta with a configurable
  distance (1..=256), encoder + decoder.

• ARC Crunch (arc_crunch, method 8, 12-bit dynamic LZW) and ARC
  Squeeze (arc_squeeze, method 4, RLE + static Huffman), encoder + decoder.

• StuffIt method 13 decoder (sit13, "LZ+Huffman"): LZSS (64 KiB window,
  LSB-first) + two per-stream 321-symbol Huffman codes switched per token,
  obtained via the fixed meta-code or one of five predefined code-length sets;
  explicit end-of-stream symbol. Decode-only. Clean-room from a facts-only
  spec, with the fixed interop tables supplied as a separately-licensed
  adjunct. Validated bit-exactly against real classic SIT! archives —
  28 method-13 forks pass the stored per-fork CRC-16, covering all five
  control modes. (Upgrades the earlier building-blocks-only Unsupported
  stub.)

  Note: lha and arc_* are clean-room from public specs and validated by
  their own encoder↔decoder round-trip, not against reference-tool output.

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This PR was generated with release-plz.