Precompute row pointers.
Remove no longer used MHA support; QStride -> qkv_dim.
Remove RowPtr from MatMul interface, use only MatPtrT.
Require opt-in define for NUQ to speed up builds.
Also fix io.cc on Windows.
PiperOrigin-RevId: 766228108
KVCache: add ctor required for MatStorageT, remove Create; bf_pre_ffw_rms_out -> pre_ffw_rms_out
optimize_test: larger vocab_size requires more steps
shared.h: Remove unused u128 type
correctly set Activation matrix rows, avoid passing as arg
ops: pass Mat instead of pointers/sizes; vectorize LayerNorm; support any weight type
mat: add OverrideRows, used by SetBatchSize
PiperOrigin-RevId: 757790736
Compression:
* Implement {any packed} x {bf16, f32} 'Load2' and DecompressAndZeroPad
* New compression test for all packed formats, add to GEMMA_TEST_FILES, remove from sfp/nuq_test
* Decompress->DecompressAndZeroPad, use PackedSpan for args with bounds checking
* NUQ: support arbitrary-length enc/dec
* New compression/shared, remove sfp.h and nuq.h
* Move Store2 into Traits and provide Compress2 wrapper
* Remove unused Decompress()-with-pool overload
* Simplify CompressedArrayLen, rename to CompressedArrayElements
* Remove unused DistortionStats b_l1_
Misc:
* Add compensated and Kahan dot, support any length
* Use same Dot function everywhere
* Move exact arithmetic functions into fp_arith
* use FloatPtr and MatPtr typedefs in tests; less stack usage
* Rename args to packed/raw
* Remove Traits::Name, instead TypeName<T>()
* Move kMaxSFP and kClusters/kGroupSize into Sfp/NuqStream
PiperOrigin-RevId: 672868468