feat: v1.1.0 — backup module, IPAM node binding, HA, task queue, theme CSS

- Backup module: full CRUD for storages, backup files, scheduled jobs (APScheduler)
- Proxmox client: storage/backup/restore/HA methods
- IPAM: proxmox_node field, server+node binding for networks and allocations
- Task queue service: improvements and new task types
- Monitoring worker: extended metrics and alerts
- HA support: add/remove VMs from Proxmox HA groups
- tasks.html: new task tracking page
- proxmox_vms.html: major UI update (bulk ops, HA, snapshots)
- backups.html: full backup management UI (3 tabs)
- base.html: sidebar backup link, websocket manager
- theme.css: full CSS variables theme, 395 lines added
- migrations: migration #15 (BackupJob), #16 (proxmox_node)
- RBAC: backup resource permissions
- websocket_manager.py: new module for WS connections

backend/app/websocket_manager.py

@@ -0,0 +1,99 @@
+"""
+WebSocket Connection Manager for real-time task updates.
+Maintains per-user WebSocket connections and broadcasts task events.
+"""
+import asyncio
+import json
+from typing import Dict, Set
+
+from fastapi import WebSocket
+from loguru import logger
+
+
+class ConnectionManager:
+    """Manages WebSocket connections grouped by user_id."""
+
+    def __init__(self):
+        # user_id -> set of active WebSocket connections
+        self._connections: Dict[int, Set[WebSocket]] = {}
+
+    async def connect(self, websocket: WebSocket, user_id: int) -> None:
+        await websocket.accept()
+        if user_id not in self._connections:
+            self._connections[user_id] = set()
+        self._connections[user_id].add(websocket)
+        logger.debug(f"[WS TASKS] User {user_id} connected ({len(self._connections[user_id])} socket(s))")
+
+    def disconnect(self, websocket: WebSocket, user_id: int) -> None:
+        if user_id in self._connections:
+            self._connections[user_id].discard(websocket)
+            if not self._connections[user_id]:
+                del self._connections[user_id]
+        logger.debug(f"[WS TASKS] User {user_id} disconnected")
+
+    @property
+    def active_user_count(self) -> int:
+        return len(self._connections)
+
+    async def send_to_user(self, user_id: int, data: dict) -> None:
+        """Send a JSON message to all WebSocket connections of a specific user."""
+        connections = self._connections.get(user_id)
+        if not connections:
+            return
+        message = json.dumps(data, default=str)
+        dead: Set[WebSocket] = set()
+        for ws in list(connections):
+            try:
+                await ws.send_text(message)
+            except Exception:
+                dead.add(ws)
+        for ws in dead:
+            self._connections[user_id].discard(ws)
+        if not self._connections.get(user_id):
+            self._connections.pop(user_id, None)
+
+    async def broadcast(self, data: dict) -> None:
+        """Send a JSON message to all connected users."""
+        message = json.dumps(data, default=str)
+        dead_pairs = []
+        for user_id, connections in list(self._connections.items()):
+            for ws in list(connections):
+                try:
+                    await ws.send_text(message)
+                except Exception:
+                    dead_pairs.append((user_id, ws))
+        for user_id, ws in dead_pairs:
+            if user_id in self._connections:
+                self._connections[user_id].discard(ws)
+
+
+# ──────────────────────────────────────────────
+# Module-level singleton used across the app
+# ──────────────────────────────────────────────
+ws_manager = ConnectionManager()
+
+
+def run_async_safe(coro) -> None:
+    """
+    Schedule an async coroutine from a synchronous background thread.
+    Used by APScheduler jobs to push WS updates without blocking.
+    """
+    try:
+        loop = asyncio.get_event_loop()
+        if loop.is_running():
+            asyncio.run_coroutine_threadsafe(coro, loop)
+        else:
+            loop.run_until_complete(coro)
+    except RuntimeError:
+        # No event loop yet (e.g. during startup); silently skip
+        pass
+
+
+def broadcast_task_update(user_id: int, event_type: str, task_data: dict) -> None:
+    """
+    Fire-and-forget WebSocket broadcast from a sync context (e.g. APScheduler).
+
+    Wraps `ws_manager.send_to_user` and schedules it on the running asyncio loop.
+    """
+    payload = {"type": event_type, "task": task_data}
+    run_async_safe(ws_manager.send_to_user(user_id, payload))