[KVCache] Per Layer Sliding Window

[joshua-j-hong]

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Adds per layer sliding window functionality to the KV Cache. Correctness is mostly achieved, but there are some cases where single tokens are strange. The corresponding MLC-LLM PR is https://github.com/mlc-ai/mlc-llm/pull/3248

A full list of changes and additions are below

• Add a new attention type for per-layer sliding window called MHA_SLIDING
• Add corresponding vectors for per-layer sliding window offset calculations
• For sliding window attention enabled KV-cache, regular sliding window is disabled to prevent page eviction
• Gemma3 has different rope parameters for local sliding window layers. This should be passed as a parameter for the KVCache, but currently these values are hardcoded