feat: 重构 agentscope 缓存架构，新增消息和附件缓存

backend/src/services/caches/interfaces.py

@@ -0,0 +1,19 @@
+from __future__ import annotations
+
+from typing import Protocol
+
+
+class CacheStore(Protocol):
+    async def hgetall(self, key: str, /) -> dict[str, str]: ...
+
+    async def hset(self, key: str, /, mapping: dict[str, str]) -> int: ...
+
+    async def hincrby(self, key: str, field: str, amount: int = 1, /) -> int: ...
+
+    async def expire(self, key: str, ttl_seconds: int, /) -> int: ...
+
+    async def delete(self, *keys: str) -> int: ...
+
+    async def sadd(self, key: str, *members: str) -> int: ...
+
+    async def smembers(self, key: str, /) -> set[str]: ...