Fix validation gaps (Resolves #3542)

[DRJ-YDV]

Fixes#3542.

This PR addresses the four validation gaps outlined in the issue:

1. Grouped GEMM Validation (gemm_grouped.h):
   Added a check in can_implement to return kErrorInvalidProblem if host_problem_sizes is null and kRequiresPrecomputation is true. This prevents host segfaults during precompute.

2. Split-K Parallel Zero Division (gemm_splitk_parallel.h):
   Added a check in can_implement to properly return kErrorInvalidProblem if split_k_slices == 0, preventing a divide-by-zero fault.

3. Batch Grid Dimension Wrapping (threadblock_swizzle.h):
   Clamped the batched grid z dimension to 65535 instead of wrapping it via modulo. This stops multiples of 65536 from producing a 0-dimension launch.

4. Sm80 EVT assert-only validation (gemm_universal_with_visitor.h):
   Replaced the debug-only assert() statements with a proper can_implement validation pass that safely returns kErrorNotSupported for Split-K Parallel, Split-K Serial, and Array GEMM modes, preventing silent garbage execution in release builds.