[Feature][main]reconstruction kvpool connector to ascend connector (#4438)

### What this PR does / why we need it?
1.In short, we renamed the existing MooncakeStoreConnector to
AscendStoreConnector and extracted the storage engine interaction logic
into a new Backend class.
Associated RFC：https://github.com/vllm-project/vllm-ascend/issues/4329
2.Fixed the issue where the number of input parameters for the connector
was incorrect, introduced in vllm 0.11.2
### Does this PR introduce _any_ user-facing change?
change MooncakeStoreConnector to AscendStoreConnector
### How was this patch tested?

- vLLM version: v0.11.2

---------

Signed-off-by: fems14 <1804143737@qq.com>

vllm_ascend/distributed/cpu_offload_connector.py

@@ -29,6 +29,7 @@ if TYPE_CHECKING:
     from vllm.attention.backends.abstract import AttentionMetadata
     from vllm.forward_context import ForwardContext
     from vllm.v1.core.kv_cache_manager import KVCacheBlocks
+    from vllm.v1.kv_cache_interface import KVCacheConfig
     from vllm.v1.request import Request
 
 
@@ -58,7 +59,10 @@ class CPUOffloadingConnectorMetadata(KVConnectorMetadata):
 
 class CPUOffloadingConnector(KVConnectorBase_V1):
 
-    def __init__(self, vllm_config: "VllmConfig", role: KVConnectorRole):
+    def __init__(self,
+                 vllm_config: VllmConfig,
+                 role: KVConnectorRole,
+                 kv_cache_config: Optional[KVCacheConfig] = None):
         if not vllm_config.cache_config.enable_prefix_caching:
             self.connector_scheduler: Optional[
                 CPUOffloadingConnectorScheduler] = None