Add kernel profiling support

For a fused kernel, we should provide detailed profiling result to show the elapsed time for each fused components, like matmul, bias_add and relu. This can help performance analysis.

No files, tests, or entry points are named. Start by locating the fused-kernel execution and profiling paths in the repository, then determine how elapsed time can be attributed to components such as matmul, bias_add, and relu. Done means a fused kernel exposes detailed per-component timing for performance analysis.

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