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>

main/proto/esp_now_messages.proto

@@ -15,12 +15,19 @@ enum EspNowMessageType {
   ESPNOW_OTA_PAYLOAD = 7;
   ESPNOW_OTA_END = 8;
   ESPNOW_OTA_STATUS = 9;
+  ESPNOW_FIND_ME = 10;
 }
 
 message EspNowUnicastTest {
   uint32 seq = 1;
 }
 
+/** Master → slave: locate pod (LED ring R/G/B ×3 @ full brightness). */
+message EspNowFindMe {
+  /** 0 = any slave; otherwise only slave_id must match */
+  uint32 client_id = 1;
+}
+
 message EspNowDiscover {
   uint32 network = 1;
 }
@@ -72,5 +79,6 @@ message EspNowMessage {
     EspNowOtaPayload ota_payload = 8;
     EspNowOtaEnd ota_end = 9;
     EspNowOtaStatus ota_status = 10;
+    EspNowFindMe find_me = 11;
   }
 }