Root cause of crashes was thread safety: libdeflate's decompressor struct
has mutable decode tables rebuilt per-block, so sharing between main thread
and FMOD audio thread caused wild writes. Fixed with a thread-local pool
keyed by Windows thread ID (FS:[0x24]).
Switched build ABI from msvc to gnu — eliminates stub headers, libdeflate
uses Zig's bundled MinGW libc. Relaxed zlib header filter from == 0x78 to
(CMF & 0x0F) == 0x08 to catch both 32K and 4K window sizes.
Benchmarked: stock=2681ms, per-call-alloc=1304ms (2.05x), tls=1194ms (2.2x)
on 84k calls. Zero errors, zero fallbacks in production.
MarcelineVQ
80a7cdea3f