fix: call gc9a01_init() in app_main to initialize display

Display was black because gc9a01_init() was never called — driver compiled
but never invoked. Init before vesc_can_init so SPI/register init completes
before TWAI claims GPIO2 (BL pin); TWAI idle=recessive=high keeps BL on.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

esp32s3/balance/main/main.c

@@ -2,6 +2,7 @@
 
 #include "orin_serial.h"
 #include "vesc_can.h"
+#include "gc9a01.h"
 #include "gitea_ota.h"
 #include "ota_self.h"
 #include "uart_ota.h"
@@ -87,7 +88,8 @@ void app_main(void)
     /* OTA rollback health check — must be called within OTA_ROLLBACK_WINDOW_S */
     ota_self_health_check();
 
-    /* Init peripherals */
+    /* Init peripherals — gc9a01 before vesc_can so BL/GPIO2 is high before TWAI takes it */
+    gc9a01_init();
     orin_serial_init();
     vesc_can_init();