[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/__init__.py

@@ -31,8 +31,13 @@ def register_connector():
 
     KVConnectorFactory.register_connector(
         "MooncakeConnectorStoreV1",
-        "vllm_ascend.distributed.mooncake.mooncake_store_connector_v1",
-        "MooncakeConnectorV1")
+        "vllm_ascend.distributed.kvpool.ascend_store_connector",
+        "AscendStoreConnector")
+
+    KVConnectorFactory.register_connector(
+        "AscendStoreConnector",
+        "vllm_ascend.distributed.kvpool.ascend_store_connector",
+        "AscendStoreConnector")
 
     KVConnectorFactory.register_connector(
         "MooncakeLayerwiseConnector",