Monorepo: Skyrim (SKSE) + Fallout 4 (F4SE) fast decompression plugins

Replaces stock zlib 1.2.7 / LZ4 r131 with:
  - libdeflate 1.25 (~2.25x faster one-shot form decompression)
  - zlib-ng 2.1.5 (SIMD-optimized streaming inflate)
  - LZ4 v1.10.0 + AVX2 (BSA/BA2 asset decompression)

Supports Skyrim SE/AE/VR and Fallout 4.