Dim LED ring, add blink mode, and signal OTA outcome on the ring.

Default brightness is ~5%; UART blink mode and green/red pulses mark OTA success or failure. Failed UART uploads skip ESP-NOW distribution.

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

goTool/cmd_led_ring.go

@@ -11,17 +11,20 @@ const (
 	ledRingModeClear    = 0
 	ledRingModeProgress = 1
 	ledRingModeDigit    = 2
+	ledRingModeBlink    = 3
 )
 
 func runLedRing(sp *serialPort, args []string) error {
 	fs := flag.NewFlagSet("led-ring", flag.ExitOnError)
-	mode := fs.String("mode", "progress", "clear, progress, or digit")
+	mode := fs.String("mode", "progress", "clear, progress, digit, or blink")
 	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")
 	g := fs.Uint("g", 255, "green 0–255")
 	b := fs.Uint("b", 0, "blue 0–255")
-	intensity := fs.Uint("intensity", 255, "brightness 0–255")
+	intensity := fs.Uint("intensity", 0, "brightness 0–255 (0 = device default ~5%)")
+	blinkMs := fs.Uint("blink-ms", 350, "pulse length in ms (mode=blink)")
+	blinkCount := fs.Uint("blink-count", 1, "number of pulses (mode=blink)")
 	if err := fs.Parse(args); err != nil {
 		return err
 	}
@@ -34,18 +37,22 @@ func runLedRing(sp *serialPort, args []string) error {
 		modeVal = ledRingModeProgress
 	case "digit":
 		modeVal = ledRingModeDigit
+	case "blink":
+		modeVal = ledRingModeBlink
 	default:
-		return fmt.Errorf("unknown -mode %q (clear, progress, digit)", *mode)
+		return fmt.Errorf("unknown -mode %q (clear, progress, digit, blink)", *mode)
 	}
 
 	resp, err := sp.ledRingProgress(&pb.LedRingProgressRequest{
-		Mode:      modeVal,
-		Progress:  uint32(*progress),
-		Digit:     uint32(*digit),
-		R:         uint32(*r),
-		G:         uint32(*g),
-		B:         uint32(*b),
-		Intensity: uint32(*intensity),
+		Mode:       modeVal,
+		Progress:   uint32(*progress),
+		Digit:      uint32(*digit),
+		R:          uint32(*r),
+		G:          uint32(*g),
+		B:          uint32(*b),
+		Intensity:  uint32(*intensity),
+		BlinkMs:    uint32(*blinkMs),
+		BlinkCount: uint32(*blinkCount),
 	})
 	if err != nil {
 		return err