Fix display refresh rate API endpoint

- Updated get_displays() to use get_available_displays() function from screen_capture module
- Removed duplicate display detection code in routes.py
- Now properly returns refresh_rate field in display API responses
- Removed unused get_monitor_names import

This fixes the "undefinedHz" issue in the Web UI by ensuring the backend properly provides refresh rate data.

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

server/src/wled_controller/api/routes.py

@@ -29,7 +29,8 @@ from wled_controller.core.calibration import (
     calibration_to_dict,
 )
 from wled_controller.storage import DeviceStore
-from wled_controller.utils import get_logger, get_monitor_names
+from wled_controller.utils import get_logger
+from wled_controller.core.screen_capture import get_available_displays
 
 logger = get_logger(__name__)
 
@@ -100,30 +101,23 @@ async def get_displays(_: AuthRequired):
     logger.info("Listing available displays")
 
     try:
-        # Import here to avoid issues if mss is not installed yet
-        import mss
+        # Get available displays with all metadata (name, refresh rate, etc.)
+        display_dataclasses = get_available_displays()
 
-        # Get friendly monitor names (Windows only, falls back to generic names)
-        monitor_names = get_monitor_names()
-
-        with mss.mss() as sct:
-            displays = []
-
-            # Skip the first monitor (it's the combined virtual screen on multi-monitor setups)
-            for idx, monitor in enumerate(sct.monitors[1:], start=0):
-                # Use friendly name from WMI if available, otherwise generic name
-                friendly_name = monitor_names.get(idx, f"Display {idx}")
-
-                display_info = DisplayInfo(
-                    index=idx,
-                    name=friendly_name,
-                    width=monitor["width"],
-                    height=monitor["height"],
-                    x=monitor["left"],
-                    y=monitor["top"],
-                    is_primary=(idx == 0),
+        # Convert dataclass DisplayInfo to Pydantic DisplayInfo
+        displays = [
+            DisplayInfo(
+                index=d.index,
+                name=d.name,
+                width=d.width,
+                height=d.height,
+                x=d.x,
+                y=d.y,
+                is_primary=d.is_primary,
+                refresh_rate=d.refresh_rate,
             )
-                displays.append(display_info)
+            for d in display_dataclasses
+        ]
 
         logger.info(f"Found {len(displays)} displays")