debug: add main.py boot/usb diagnostic prints

Add prints before/after boot import, usb import, usb.bus.open, and
StatusBar to pinpoint where execution stalls — ConnectionRefusedError
indicates usb.bus.open() is never reached.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: wabicai

test/data/onekey-firmware-build.patch

@@ -256,17 +256,36 @@ index 2bf17e049..8d0540bde 100644
 
  def store_ble_name(ble_name):
 diff --git a/core/src/main.py b/core/src/main.py
-index 511b4fe43..5d598f1b8 100644
+index 511b4fe43..53f38e1c2 100644
 --- a/core/src/main.py
 +++ b/core/src/main.py
-@@ -51,7 +51,6 @@ import usb  # noqa: F401
+@@ -39,21 +39,25 @@ import trezor.pin  # noqa: F401
+ unimport_manager = utils.unimport()
+ 
+ # unlock the device, unload the boot module afterwards
++print("DBG main: before boot import")
+ with unimport_manager:
+     import boot
+     del boot
++print("DBG main: boot done")
+ 
+ # === Prepare the USB interfaces first. Do not connect to the host yet.
+ # usb imports trezor.utils and trezor.io which is a C module
+ import usb  # noqa: F401
++print("DBG main: usb imported")
+ 
+ # start the USB
  import storage.device
  usb.bus.open(storage.device.get_device_id())
- 
 -
++print("DBG main: usb.bus.open done")
+ 
  # initialize the status bar
  StatusBar.get_instance()
++print("DBG main: StatusBar done, entering loop")
 
+ # run the endless loop
+ while True:
 diff --git a/core/src/session.py b/core/src/session.py
 index 1fb029830..b3e5960b0 100644
 --- a/core/src/session.py