fix initial usb crash with a delay

hello_usb.cpp

@@ -451,6 +451,8 @@ void tuh_hid_report_received_cb(uint8_t dev_addr, uint8_t instance, uint8_t cons
 
 int main() {
     stdio_init_all();
+    sleep_ms(3000); // Give time for power to settle and serial to connect
+    printf("System Booting...\n");
     
     // Launch display initialization on core 1
     printf("Launching e-Paper display init on core 1...\n");
@@ -464,9 +466,17 @@ int main() {
     
     printf("Initializing TinyUSB Host...\n");
     tuh_init(BOARD_TUH_RHPORT);
+    printf("TinyUSB Host Initialized.\n");
 
+    uint32_t last_print = 0;
     while (true) {
         tuh_task();
+        
+        uint32_t now = to_ms_since_boot(get_absolute_time());
+        if (now - last_print > 5000) {
+            printf("Heartbeat: %u\n", now);
+            last_print = now;
+        }
     }
 
     return 0;