### What this PR does / why we need it? Mooncake layerwise connector supports Mamba prefix caching on prefiller nodes. ### Does this PR introduce _any_ user-facing change? Yes. Use `--enable-prefix-caching` and `--mamba-cache-mode align` to enable mamba align mode prefix caching on P/D prefill nodes. This function does not supports on decode nodes now. ### How was this patch tested? By P/D E2E test. --------- Signed-off-by: nwpu-zxr <zhouxuerong2@huawei.com>