refactor(hicache): Introduce generic HiCacheStorageConfig for improved configuration management (#9555)

Co-authored-by: Teng Ma <805522925@qq.com>

python/sglang/srt/mem_cache/hiradix_cache.py

@@ -39,6 +39,8 @@ class HiRadixCache(RadixCache):
         hicache_mem_layout: str,
         hicache_storage_backend: Optional[str] = None,
         hicache_storage_prefetch_policy: Optional[str] = "best_effort",
+        model_name: Optional[str] = None,
+        storage_backend_extra_config: Optional[str] = None,
     ):
 
         if hicache_io_backend == "direct":
@@ -87,6 +89,8 @@ class HiRadixCache(RadixCache):
             io_backend=hicache_io_backend,
             storage_backend=hicache_storage_backend,
             prefetch_threshold=self.prefetch_threshold,
+            model_name=model_name,
+            storage_backend_extra_config=storage_backend_extra_config,
         )
 
         # record the nodes with ongoing write through