Remove idle color feature, simplify power to turn-off only, fix settings serial port bug

- Remove static/idle color from entire stack (storage, API, processing, UI, CSS, locales)
- Simplify device power button to turn-off only (send black frame, no toggle)
- Send black frame on serial port close (AdalightClient.close)
- Fix settings modal serial port dropdown showing WLED devices due to stale deviceType

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

server/src/wled_controller/core/devices/adalight_client.py

@@ -100,7 +100,14 @@ class AdalightClient(LEDClient):
             raise RuntimeError(f"Failed to open serial port {self._port}: {e}")
 
     async def close(self) -> None:
-        """Close the serial port."""
+        """Send black frame and close the serial port."""
+        if self._connected and self._serial and self._serial.is_open and self._led_count > 0:
+            try:
+                black = np.zeros((self._led_count, 3), dtype=np.uint8)
+                frame = self._build_frame(black, brightness=255)
+                await asyncio.to_thread(self._serial.write, frame)
+            except Exception as e:
+                logger.debug(f"Failed to send black frame on close: {e}")
         self._connected = False
         if self._serial and self._serial.is_open:
             try:

server/src/wled_controller/core/devices/serial_provider.py

@@ -2,10 +2,10 @@
 
 Subclasses only need to override ``device_type`` and ``create_client()``.
 All common serial-device logic (COM port validation, discovery, health
-checks, power control via black frames, static colour) lives here.
+checks, power control via black frames) lives here.
 """
 
-from typing import List, Tuple
+from typing import List
 
 import numpy as np
 
@@ -28,8 +28,7 @@ class SerialDeviceProvider(LEDDeviceProvider):
         # manual_led_count: user must specify LED count (can't auto-detect)
         # power_control: can blank LEDs by sending all-black pixels
         # brightness_control: software brightness (multiplies pixel values before sending)
-        # static_color: can send a solid colour frame
-        return {"manual_led_count", "power_control", "brightness_control", "static_color"}
+        return {"manual_led_count", "power_control", "brightness_control"}
 
     async def check_health(self, url: str, http_client, prev_health=None) -> DeviceHealth:
         # Generic serial port health check — enumerate COM ports
@@ -116,31 +115,3 @@ class SerialDeviceProvider(LEDDeviceProvider):
         finally:
             await client.close()
 
-    async def set_color(self, url: str, color: Tuple[int, int, int], **kwargs) -> None:
-        """Send a solid color frame to the device.
-
-        Accepts optional kwargs:
-            client: An already-connected LEDClient (e.g. cached idle client).
-            brightness (int): Software brightness 0-255 (default 255).
-            led_count (int), baud_rate (int | None).
-        """
-        led_count = kwargs.get("led_count", 0)
-        if led_count <= 0:
-            raise ValueError(f"led_count is required to send color frame to {self.device_type} device")
-
-        brightness = kwargs.get("brightness", 255)
-        frame = np.full((led_count, 3), color, dtype=np.uint8)
-
-        existing_client = kwargs.get("client")
-        if existing_client:
-            await existing_client.send_pixels(frame, brightness=brightness)
-        else:
-            baud_rate = kwargs.get("baud_rate")
-            client = self.create_client(url, led_count=led_count, baud_rate=baud_rate)
-            try:
-                await client.connect()
-                await client.send_pixels(frame, brightness=brightness)
-            finally:
-                await client.close()
-
-        logger.info(f"{self.device_type} set_color: sent solid {color} to {url}")