refactor: 重构 AgentScope ReAct Runner 与事件处理

- 重构 runtime/runner.py 实现 ReAct Agent 核心逻辑
- 更新事件编码器与存储机制
- 优化 prompt 系统与 tool 调用
- 调整 agent service 与 repository 配合

backend/src/v1/friendships/repository.py

@@ -53,6 +53,12 @@ class FriendshipRepository(Protocol):
         """Get friendship by ID."""
         ...
 
+    async def get_friendships_by_ids(
+        self, friendship_ids: list[UUID]
+    ) -> dict[UUID, Friendship]:
+        """Batch get friendships by IDs."""
+        ...
+
     async def get_inbox_messages_for_user(
         self, user_id: UUID, status: InboxMessageStatus | None = None
     ) -> list[InboxMessage]:
@@ -214,6 +220,28 @@ class SQLAlchemyFriendshipRepository(BaseRepository[Friendship]):
             )
             raise
 
+    async def get_friendships_by_ids(
+        self, friendship_ids: list[UUID]
+    ) -> dict[UUID, Friendship]:
+        if not friendship_ids:
+            return {}
+        try:
+            unique_ids = list(dict.fromkeys(friendship_ids))
+            stmt = (
+                select(Friendship)
+                .where(Friendship.id.in_(unique_ids))
+                .where(Friendship.deleted_at.is_(None))
+            )
+            result = await self._session.execute(stmt)
+            friendships = list(result.scalars().all())
+            return {friendship.id: friendship for friendship in friendships}
+        except SQLAlchemyError:
+            logger.exception(
+                "Failed to get friendships by ids",
+                friendship_ids=[str(i) for i in friendship_ids],
+            )
+            raise
+
     async def get_inbox_messages_for_user(
         self, user_id: UUID, status: InboxMessageStatus | None = None
     ) -> list[InboxMessage]:

backend/src/v1/friendships/service.py

@@ -362,6 +362,28 @@ class FriendshipService(BaseService):
                 status_code=503, detail="Friendship service unavailable"
             )
 
+        candidate_inbox = [
+            inbox
+            for inbox in inbox_messages
+            if inbox.message_type == InboxMessageType.FRIEND_REQUEST
+            and inbox.friendship_id is not None
+            and inbox.sender_id is not None
+        ]
+        if not candidate_inbox:
+            return []
+
+        friendship_ids = [inbox.friendship_id for inbox in candidate_inbox]
+        friendships_by_id = await self._repository.get_friendships_by_ids(
+            cast(list[UUID], friendship_ids)
+        )
+
+        profile_ids = {user_id}
+        for inbox in candidate_inbox:
+            sender_id = cast(UUID, inbox.sender_id)
+            profile_ids.add(sender_id)
+        profiles_by_id = await self._user_repository.get_by_user_ids(list(profile_ids))
+        recipient = profiles_by_id.get(user_id)
+
         result: list[FriendRequestResponse] = []
         for inbox in inbox_messages:
             if inbox.message_type != InboxMessageType.FRIEND_REQUEST:
@@ -371,7 +393,7 @@ class FriendshipService(BaseService):
             if friendship_id is None:
                 continue
 
-            friendship = await self._repository.get_friendship_by_id(friendship_id)
+            friendship = friendships_by_id.get(friendship_id)
             if friendship is None or friendship.status != FriendshipStatus.PENDING:
                 continue
 
@@ -379,8 +401,7 @@ class FriendshipService(BaseService):
             if sender_id is None:
                 continue
 
-            sender = await self._user_repository.get_by_user_id(sender_id)
-            recipient = await self._user_repository.get_by_user_id(user_id)
+            sender = profiles_by_id.get(sender_id)
 
             result.append(
                 FriendRequestResponse(
@@ -460,11 +481,19 @@ class FriendshipService(BaseService):
                 status_code=503, detail="Friendship service unavailable"
             )
 
+        if not outgoing:
+            return []
+
+        user_ids = {user_id}
+        for friendship in outgoing:
+            user_ids.add(self._get_other_user_id(friendship, user_id))
+        profiles_by_id = await self._user_repository.get_by_user_ids(list(user_ids))
+        sender = profiles_by_id.get(user_id)
+
         result: list[FriendRequestResponse] = []
         for friendship in outgoing:
             other_user_id = self._get_other_user_id(friendship, user_id)
-            sender = await self._user_repository.get_by_user_id(user_id)
-            recipient = await self._user_repository.get_by_user_id(other_user_id)
+            recipient = profiles_by_id.get(other_user_id)
 
             result.append(
                 FriendRequestResponse(
@@ -489,10 +518,18 @@ class FriendshipService(BaseService):
                 status_code=503, detail="Friendship service unavailable"
             )
 
+        if not friendships:
+            return []
+
+        friend_ids = [
+            self._get_other_user_id(friendship, user_id) for friendship in friendships
+        ]
+        profiles_by_id = await self._user_repository.get_by_user_ids(friend_ids)
+
         result: list[FriendResponse] = []
         for friendship in friendships:
             friend_id = self._get_other_user_id(friendship, user_id)
-            friend = await self._user_repository.get_by_user_id(friend_id)
+            friend = profiles_by_id.get(friend_id)
 
             result.append(
                 FriendResponse(