cuda : CUDA GGML_OP_LIGHTNING_INDEXER implementation (generic vector kernel + wmma...

cuda : CUDA GGML_OP_LIGHTNING_INDEXER implementation (generic vector kernel + wmma kernel) (#25545)

* cuda : CUDA GGML_OP_LIGHTNING_INDEXER implementation (generic vector kernel + wmma kernel)

* chore : remove indentation of #pragma unroll

* cuda : remove unnecessary kernel template declarations

* cuda : add WARPS_PER_BLOCK and K_VECS_PER_BLOCK template parameters in lightning indexer kernels to avoid duplication of constants.

* cuda : relax MMA architecture requirements to Turing in lightning indexer implementation

* chore : renamed variables

* chore : rename ggml_cuda_op_lightning_indexer() to ggml_cuda_lightning_indexer()

* chore : TODO for AMD rocWMMA

* chore : whitespace formatting

* chore : another variable rename to fix problems caused by shadowing

* chore : yet another rename, this time uppercased all constants

* cuda : added alignment checks for Q and K tensors in lightning indexer implementation

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Co-authored-by: Stanisław Szymczyk <redacted>