Add software brightness control for Adalight devices

Emulates hardware brightness by multiplying pixel values before serial
send. Stored per-device and persisted across restarts.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

server/src/wled_controller/api/routes/devices.py

@@ -323,8 +323,9 @@ async def get_device_brightness(
     device_id: str,
     _auth: AuthRequired,
     store: DeviceStore = Depends(get_device_store),
+    manager: ProcessorManager = Depends(get_processor_manager),
 ):
-    """Get current brightness from the WLED device."""
+    """Get current brightness from the device."""
     device = store.get_device(device_id)
     if not device:
         raise HTTPException(status_code=404, detail=f"Device {device_id} not found")
@@ -332,6 +333,8 @@ async def get_device_brightness(
         raise HTTPException(status_code=400, detail=f"Brightness control is not supported for {device.device_type} devices")
 
     try:
+        if device.device_type == "adalight":
+            return {"brightness": device.software_brightness}
         provider = get_provider(device.device_type)
         bri = await provider.get_brightness(device.url)
         return {"brightness": bri}
@@ -346,8 +349,9 @@ async def set_device_brightness(
     body: dict,
     _auth: AuthRequired,
     store: DeviceStore = Depends(get_device_store),
+    manager: ProcessorManager = Depends(get_processor_manager),
 ):
-    """Set brightness on the WLED device directly."""
+    """Set brightness on the device."""
     device = store.get_device(device_id)
     if not device:
         raise HTTPException(status_code=404, detail=f"Device {device_id} not found")
@@ -359,6 +363,14 @@ async def set_device_brightness(
         raise HTTPException(status_code=400, detail="brightness must be an integer 0-255")
 
     try:
+        if device.device_type == "adalight":
+            device.software_brightness = bri
+            device.updated_at = __import__("datetime").datetime.utcnow()
+            store.save()
+            # Update runtime state so the processing loop picks it up
+            if device_id in manager._devices:
+                manager._devices[device_id].software_brightness = bri
+            return {"brightness": bri}
         provider = get_provider(device.device_type)
         await provider.set_brightness(device.url, bri)
         return {"brightness": bri}