fix: Remove outer try-catch block from signals endpoint

- Removed the outer try-catch block that was catching HTTPException
- HTTPException now properly propagates to FastAPI error handler
- This ensures clear error messages are returned when protocol servers are disabled

src/dashboard/api.py

@@ -601,7 +601,6 @@ async def _generate_mock_signals(stations: Dict, pumps_by_station: Dict) -> List
 @dashboard_router.get("/signals")
 async def get_signals():
     """Get overview of all active signals across protocols"""
-    try:
     # Use default stations and pumps since we don't have db access in this context
     stations = {
         "STATION_001": {"name": "Main Pump Station", "location": "Downtown"},
@@ -720,10 +719,6 @@ async def get_signals():
         "last_updated": datetime.now().isoformat()
     }
 
-    except Exception as e:
-        logger.error(f"Error getting signals: {str(e)}")
-        raise HTTPException(status_code=500, detail=f"Failed to get signals: {str(e)}")
-
 @dashboard_router.get("/signals/export")
 async def export_signals():
     """Export signals to CSV format"""