feat: Added the ability to use custom button icons

Override_buttons.md

@@ -1,17 +1,20 @@
 ## Overriding key actions
 
+You can override the default behavior of any button to call a different Home Assistant service. You can also customize the icon and style for media control buttons (PLAY, PAUSE, STOP, REWIND, RECORD, FAST_FOWARD).
+
 Example config:
+
 ```yaml
 type: custom:lg-remote-control
 av_receiver_family: anthemav
 entity: media_player.lg_webos_smart_tv
-is_smart_tv: 'true'
+is_smart_tv: "true"
 colors:
   buttons: red
   text: blue
   background: blue
-projectorentity: ''
-mac: '00:11:22:33:44:66'
+projectorentity: ""
+mac: "00:11:22:33:44:66"
 keys:
   LEFT:
     service: light.toggle
@@ -23,7 +26,58 @@ keys:
       entity_id: light.tv
 ```
 
-available keys:
+### Customizing media control buttons (icons and style)
+
+For media control buttons (PLAY, PAUSE, STOP, REWIND, RECORD, FAST_FOWARD), you can also customize the icon and button style. This is useful for repurposing these buttons for other functions like receiver volume control:
+
+```yaml
+type: custom:lg-remote-control
+entity: media_player.lg_webos_smart_tv
+keys:
+  PLAY:
+    icon: mdi:volume-high
+    service: media_player.volume_up
+    data:
+      entity_id: media_player.receiver
+  PAUSE:
+    icon: mdi:volume-medium
+    service: media_player.volume_mute
+    data:
+      entity_id: media_player.receiver
+  STOP:
+    icon: mdi:volume-low
+    service: media_player.volume_down
+    data:
+      entity_id: media_player.receiver
+  REWIND:
+    icon: mdi:skip-previous
+    service: media_player.media_previous_track
+    data:
+      entity_id: media_player.receiver
+  RECORD:
+    icon: mdi:power
+    style: color: green;
+    service: media_player.toggle
+    data:
+      entity_id: media_player.receiver
+  FAST_FOWARD:
+    icon: mdi:skip-next
+    service: media_player.media_next_track
+    data:
+      entity_id: media_player.receiver
+```
+
+### Key configuration options
+
+| Property  | Description                                                        |
+| --------- | ------------------------------------------------------------------ |
+| `service` | Home Assistant service to call (e.g., `media_player.volume_up`)    |
+| `data`    | Service data to pass (e.g., `entity_id: media_player.receiver`)    |
+| `icon`    | Custom icon for media control buttons (e.g., `mdi:volume-high`)    |
+| `style`   | Custom CSS style for media control buttons (e.g., `color: green;`) |
+
+### Available keys:
+
 - `"1"`
 - `"2"`
 - `"3"`