metal: per-op source split + parallel compile (#26561)
* metal : per-op source split + parallel compile (#24021)
* preliminary extract common header
* op source split
* split metallib into 8 libs && load in parallel
* derive kernel->library routing from functionNames
* x-macro lib list + underscore filenames, dedup QK_NL, MRC fixes
* op source split 8 to 20
* improve robustness of source fallback
* clean up
* change bool -> atomic_bool
* only prepend headers that source actually includes
* no semaphore, use GCD global queue
* dedup library compile path, fix NSError lifetime, rename gla
* relocate upstream concat/rope_back/repeat kernel changes into split files
* move ggml-common.h from common.h into dequantize.h to shrink binary size
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Co-authored-by: lvyichen <lvyichen@stepfun.com>
* metal: add col2im_1d op (f32/f16/bf16) (#25176)
* metal : add set_rows with src0 f16 (#25434)
* metal : add CONV_2D_DW (depthwise convolution) support (#21565)
* metal : add Q2_0 support (#25419)
* metal: fuse snake activation (mul, sin, sqr, mul, add) (#25459)
* ggml-metal: FWHT kernel for metal backend (#25924)
* metal : port new kernels into the split sources
Move the kernels added on master after the split (lightning indexer,
DSv4 hyper-connections, silu_back, f16 bin ops, TQ2_0, the flash-attn KV
dequantization pass, rope offset/inplace, ssm_scan rollback, packed q8_0
dequantization and the tensor-API mat-mat K clamp) into the corresponding
kernels/*.metal sources. Copied verbatim, no functional change.
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Co-authored-by: lvyichen <lvyichen@stepfun.com>
Co-authored-by: Georgi Gerganov <ggerganov@gmail.com>
