Add find-me LED locate on master and slaves via ESP-NOW.

UART FIND_ME (client_id 0 = local ring, >0 = unicast), ESPNOW_FIND_ME payload, CLI/dashboard buttons per slave.

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

goTool/cmd_led_ring.go

@@ -12,11 +12,12 @@ const (
 	ledRingModeProgress = 1
 	ledRingModeDigit    = 2
 	ledRingModeBlink    = 3
+	ledRingModeFindMe   = 4
 )
 
 func runLedRing(sp *serialPort, args []string) error {
 	fs := flag.NewFlagSet("led-ring", flag.ExitOnError)
-	mode := fs.String("mode", "progress", "clear, progress, digit, or blink")
+	mode := fs.String("mode", "progress", "clear, progress, digit, blink, or find-me")
 	progress := fs.Uint("progress", 0, "fill level 0–100 (mode=progress)")
 	digit := fs.Uint("digit", 0, "digit 0–10 (mode=digit)")
 	r := fs.Uint("r", 0, "red 0–255")
@@ -39,8 +40,10 @@ func runLedRing(sp *serialPort, args []string) error {
 		modeVal = ledRingModeDigit
 	case "blink":
 		modeVal = ledRingModeBlink
+	case "find-me", "find_me", "findme":
+		modeVal = ledRingModeFindMe
 	default:
-		return fmt.Errorf("unknown -mode %q (clear, progress, digit, blink)", *mode)
+		return fmt.Errorf("unknown -mode %q (clear, progress, digit, blink, find-me)", *mode)
 	}
 
 	resp, err := sp.ledRingProgress(&pb.LedRingProgressRequest{