Add LED ring control per client and broadcast over REST and WebSocket.

Solid color mode fills all ring LEDs; master routes UART commands to slaves
via ESPNOW_LED_RING. goTool exposes POST /api/led-ring, WebSocket set_led_ring,
and a dashboard LED panel with master/slave/all targets.

Co-authored-by: Cursor <cursoragent@cursor.com>

main/cmd/cmd_led_ring.h

@@ -1,6 +1,12 @@
 #ifndef CMD_LED_RING_H
 #define CMD_LED_RING_H
 
+#include <stdbool.h>
+#include "uart_messages.pb.h"
+
+/** Apply LED ring command locally (master or slave). */
+bool cmd_led_ring_apply(const alox_LedRingProgressRequest *req);
+
 void cmd_led_ring_register(void);
 
 #endif