Merge remote-tracking branch 'origin/v3' into v3

# Conflicts:
#	app/api/endpoints/agent.py
#	app/api/endpoints/anthropic.py
#	app/api/endpoints/openai.py
#	app/chain/__init__.py
#	app/chain/message.py
#	app/chain/site.py
#	app/chain/subscribe.py
#	app/chain/transfer.py
#	app/modules/discord/__init__.py
#	app/modules/qqbot/__init__.py
#	app/modules/slack/__init__.py
#	app/modules/telegram/__init__.py
#	app/modules/wechat/__init__.py
#	app/runtime/extensions/module_manager.py
#	app/runtime/extensions/service_registry.py
#	tests/test_agent_interaction.py
#	tests/test_slash_command_interactions.py
#	tests/test_web_agent_stream.py

app/chain/_interaction.py

@@ -0,0 +1,86 @@
+from typing import Optional, Tuple, Union
+
+from app.schemas.types import NotificationChannel
+
+
+class InteractionChainMixin:
+    """
+    斜杠命令交互四件套委托：remote_list / parse_callback /
+    handle_callback_interaction / handle_text_interaction。
+
+    subscribe、site 等业务链的交互入口完全同构，唯一差异是各自的
+    交互处理器构造参数。本 mixin 将四件套委托提取为公共实现，
+    子类只需注入处理器类并实现 _interaction_handler 构造器。
+
+    子类注入约定：
+    - `_interaction_handler_type`：交互处理器类，提供静态 parse_callback；
+    - `_interaction_handler()`：按各链业务动作构造处理器实例。
+    """
+
+    # 交互处理器类，子类注入（如 SubscribeInteractionHandler / SiteInteractionHandler）
+    _interaction_handler_type: type = None
+
+    def _interaction_handler(self):
+        """
+        构造交互处理器实例，由子类按各自业务动作注入实现。
+        """
+        raise NotImplementedError
+
+    def remote_list(
+            self,
+            arg_str: str = "",
+            channel: NotificationChannel = None,
+            userid: Union[str, int] = None,
+            source: Optional[str] = None,
+    ):
+        """
+        斜杠命令统一入口，委托交互处理器。
+        """
+        return self._interaction_handler().remote_list(
+            arg_str=arg_str, channel=channel, userid=userid, source=source
+        )
+
+    @classmethod
+    def parse_callback(cls, callback_data: str) -> Optional[Tuple[str, str]]:
+        """
+        解析斜杠命令按钮回调。
+        """
+        return cls._interaction_handler_type.parse_callback(callback_data)
+
+    def handle_callback_interaction(
+            self,
+            callback_data: str,
+            channel: NotificationChannel,
+            source: str,
+            userid: Union[str, int],
+            username: str,
+            original_message_id: Optional[Union[str, int]] = None,
+            original_chat_id: Optional[str] = None,
+    ) -> bool:
+        """委托交互处理器处理按钮回调。"""
+        return self._interaction_handler().handle_callback_interaction(
+            callback_data=callback_data,
+            channel=channel,
+            source=source,
+            userid=userid,
+            username=username,
+            original_message_id=original_message_id,
+            original_chat_id=original_chat_id,
+        )
+
+    def handle_text_interaction(
+            self,
+            channel: NotificationChannel,
+            source: str,
+            userid: Union[str, int],
+            username: str,
+            text: str,
+    ) -> bool:
+        """委托交互处理器处理文本输入。"""
+        return self._interaction_handler().handle_text_interaction(
+            channel=channel,
+            source=source,
+            userid=userid,
+            username=username,
+            text=text,
+        )