refactor: rename plugin manager to plugin client and rename path from manager to impl (#18876)

api/core/plugin/impl/asset.py

@@ -0,0 +1,12 @@
+from core.plugin.impl.base import BasePluginClient
+
+
+class PluginAssetManager(BasePluginClient):
+    def fetch_asset(self, tenant_id: str, id: str) -> bytes:
+        """
+        Fetch an asset by id.
+        """
+        response = self._request(method="GET", path=f"plugin/{tenant_id}/asset/{id}")
+        if response.status_code != 200:
+            raise ValueError(f"can not found asset {id}")
+        return response.content