feat(huya): 协作台账增加 WebSocket 实时同步

- 后端新增进程内事件总线与 /api/huya/external-orders/ws\n- 所有写接口成功后发布轻量失效事件\n- 前端自动重连、静默刷新、断线兜底轮询

web/backend/services/huya_collab_events.py

@@ -0,0 +1,104 @@
+"""虎牙外部单协作台账的进程内实时事件总线。
+
+写接口提交成功后只发布「台账失效」事件，前端收到后按自己的筛选条件静默重拉，
+不在事件里携带整行数据。当前生产是单 uvicorn worker，进程内队列足够；
+如果以后改成多 worker / 多实例，这里再换成 Redis Pub/Sub。
+"""
+
+from __future__ import annotations
+
+import asyncio
+import itertools
+import threading
+from datetime import UTC, datetime
+from typing import Any
+
+
+class CollabEventHub:
+    """维护 revision 与当前 WebSocket 订阅队列。"""
+
+    def __init__(self) -> None:
+        self._lock = threading.Lock()
+        self._revisions = itertools.count(1)
+        self._current_revision = 0
+        self._loop: asyncio.AbstractEventLoop | None = None
+        self._subscribers: set[asyncio.Queue[dict[str, Any]]] = set()
+
+    @property
+    def revision(self) -> int:
+        with self._lock:
+            return self._current_revision
+
+    def subscribe(self) -> asyncio.Queue[dict[str, Any]]:
+        """注册一个 WebSocket 订阅者；必须在事件循环线程里调用。"""
+        loop = asyncio.get_running_loop()
+        queue: asyncio.Queue[dict[str, Any]] = asyncio.Queue(maxsize=100)
+        with self._lock:
+            self._loop = loop
+            self._subscribers.add(queue)
+        return queue
+
+    def unsubscribe(self, queue: asyncio.Queue[dict[str, Any]]) -> None:
+        with self._lock:
+            self._subscribers.discard(queue)
+
+    def ready_event(self) -> dict[str, Any]:
+        with self._lock:
+            revision = self._current_revision
+        return {"type": "collab.ready", "revision": revision}
+
+    def ping_event(self) -> dict[str, Any]:
+        with self._lock:
+            revision = self._current_revision
+        return {"type": "collab.ping", "revision": revision}
+
+    def publish(
+        self,
+        *,
+        scope: str,
+        action: str,
+        actor_id: int | None = None,
+        orders: list[dict[str, int]] | None = None,
+    ) -> dict[str, Any]:
+        """发布一次失效事件；同步接口在线程池里调用也安全。"""
+        with self._lock:
+            revision = next(self._revisions)
+            self._current_revision = revision
+            loop = self._loop
+            subscribers = list(self._subscribers)
+
+        event = {
+            "type": "collab.invalidate",
+            "revision": revision,
+            "scope": scope,
+            "action": action,
+            "actor_id": actor_id,
+            "orders": orders or [],
+            "at": datetime.now(UTC).isoformat(),
+        }
+        if loop is None or not subscribers:
+            return event
+
+        for queue in subscribers:
+            try:
+                loop.call_soon_threadsafe(self._offer, queue, event)
+            except RuntimeError:
+                # 事件循环已经关闭：忽略，下次连接会重新拉全量。
+                continue
+        return event
+
+    @staticmethod
+    def _offer(queue: asyncio.Queue[dict[str, Any]], event: dict[str, Any]) -> None:
+        """队列满时丢掉旧事件，保留最新一次失效通知。"""
+        while queue.full():
+            try:
+                queue.get_nowait()
+            except asyncio.QueueEmpty:
+                break
+        try:
+            queue.put_nowait(event)
+        except asyncio.QueueFull:
+            pass
+
+
+collab_events = CollabEventHub()