feat: complete Phase 1 MVP - add agent executor and WebSocket real-time updates

Agent Executor Service:
- BaseAgent class with LLM integration via LiteLLM proxy
- AgentExecutor service that processes pending executions every 5 seconds
- Action execution: create_subtask, update_status, send_notification, add_comment
- Approval workflow: CxO level agents require user approval before execution
- Telegram notifications for approvals and completions
- Error handling and execution status tracking

WebSocket Real-Time Updates:
- WebSocket endpoint at /ws/opc for real-time task updates
- ConnectionManager for broadcasting to all connected clients
- Frontend WebSocket client with auto-reconnect
- Live updates for task create/update/move/delete actions
- Agent execution status broadcasts

Integration:
- Agent executor starts on dashboard startup
- Task router broadcasts WebSocket updates on all mutations
- Frontend OPC page subscribes to WebSocket and updates UI in real-time
- Agents (PM, CTO, COO) can now execute tasks autonomously

Phase 1 MVP Complete:
✅ PostgreSQL database with full schema
✅ Task CRUD API with automatic time tracking
✅ Kanban board with drag-and-drop
✅ Agent executor service with LLM integration
✅ WebSocket real-time updates
✅ 3 core agents ready to execute

Next: Agent panel UI, email notifications, PDF invoicing

dashboard/backend/routers/opc_ws.py

@@ -0,0 +1,107 @@
+"""
+OPC WebSocket Router - Real-time updates for tasks and agent executions
+"""
+from fastapi import APIRouter, WebSocket, WebSocketDisconnect, Depends
+from typing import Set
+import json
+import asyncio
+import logging
+from auth import get_current_user_ws
+
+logger = logging.getLogger(__name__)
+
+router = APIRouter()
+
+# Active WebSocket connections
+active_connections: Set[WebSocket] = set()
+
+
+class ConnectionManager:
+    """Manages WebSocket connections"""
+
+    def __init__(self):
+        self.active_connections: Set[WebSocket] = set()
+
+    async def connect(self, websocket: WebSocket):
+        """Accept and register a new connection"""
+        await websocket.accept()
+        self.active_connections.add(websocket)
+        logger.info(f"WebSocket connected. Total connections: {len(self.active_connections)}")
+
+    def disconnect(self, websocket: WebSocket):
+        """Remove a connection"""
+        self.active_connections.discard(websocket)
+        logger.info(f"WebSocket disconnected. Total connections: {len(self.active_connections)}")
+
+    async def broadcast(self, message: dict):
+        """Broadcast message to all connected clients"""
+        disconnected = set()
+        for connection in self.active_connections:
+            try:
+                await connection.send_json(message)
+            except Exception as e:
+                logger.error(f"Failed to send message: {e}")
+                disconnected.add(connection)
+
+        # Clean up disconnected clients
+        for conn in disconnected:
+            self.disconnect(conn)
+
+
+manager = ConnectionManager()
+
+
+@router.websocket("/ws")
+async def websocket_endpoint(websocket: WebSocket):
+    """WebSocket endpoint for OPC real-time updates"""
+    await manager.connect(websocket)
+
+    try:
+        while True:
+            # Keep connection alive and receive any client messages
+            data = await websocket.receive_text()
+
+            # Echo back for ping/pong
+            if data == "ping":
+                await websocket.send_text("pong")
+
+    except WebSocketDisconnect:
+        manager.disconnect(websocket)
+    except Exception as e:
+        logger.error(f"WebSocket error: {e}")
+        manager.disconnect(websocket)
+
+
+async def broadcast_task_update(task_id: int, action: str, task_data: dict):
+    """Broadcast task update to all connected clients"""
+    message = {
+        "type": "task_update",
+        "task_id": task_id,
+        "action": action,  # created, updated, moved, deleted
+        "data": task_data,
+        "timestamp": task_data.get("updated_at")
+    }
+    await manager.broadcast(message)
+
+
+async def broadcast_agent_execution(execution_id: int, status: str, execution_data: dict):
+    """Broadcast agent execution update"""
+    message = {
+        "type": "agent_execution",
+        "execution_id": execution_id,
+        "status": status,  # pending, running, completed, failed, pending_approval
+        "data": execution_data,
+        "timestamp": execution_data.get("started_at") or execution_data.get("completed_at")
+    }
+    await manager.broadcast(message)
+
+
+async def broadcast_agent_status(agent_id: str, status: str, message_text: str = ""):
+    """Broadcast agent status update"""
+    message = {
+        "type": "agent_status",
+        "agent_id": agent_id,
+        "status": status,  # idle, working, error
+        "message": message_text
+    }
+    await manager.broadcast(message)