v0.4.2

Security fixes, SIMD improvements, i686 correctness

Security Fixes (PR #4)

• Default WebPDecoder to Limits::default() instead of Limits::none() — prevents unbounded memory use on adversarial input
• Wire up frame count checking during ANMF chunk parsing
• Cap num_huff_groups to prevent memory amplification from malformed lossless streams
• Replace assert! panics with error returns in lossless transforms and Huffman table build
• Bounds-check VP8 chunk range before slicing

SIMD Additions

• NEON and WASM128 dispatch for lossless predictor transforms and add_green_to_blue_and_red
• NEON and WASM128 dispatch for encoder lossless transforms
• Lossless inverse transforms upgraded to AVX2 (v3) via u8x32 wide SIMD
• Monolithic V3 #[arcane] entry with #[rite] wrappers for all predictors — enables LLVM autovectorization of scalar loops with AVX2 target_feature
• Fused chroma-upsample + YUV→RGB kernel wired into v2 decoder

Bug Fixes

• Fix chroma interpolation in scalar fallback for fused_row_2uv — 4-tap interpolation was collapsed to 2-tap for even luma positions on i686 (all YUV bit-exact tests now pass on 32-bit targets)

Dependencies

• Update zencodec to 0.1.12, archmage/magetypes to 0.9.16