JUC500 offline update
XFER_BUILD=2026-07-20-smartkmlink3
created=20260720-144424
SmartKMLink VID:PID=0ea0:7301 (IF5 same as JUC500)

Windows closed-network apply:
  1) Copy this folder (or unzip) to the peer PC via USB stick
  2) Close JUC500 GUI on Windows
  3) Double-click apply_offline_update.bat
     (default DEST=C:\dev\juc500 — or: apply_offline_update.bat D:\path\juc500)
  4) cd C:\dev\juc500 && start.bat
  5) GUI version line must show: 2026-07-20-smartkmlink3
  6) SmartKMLink / JUC500 IF5: vendor\tools\zadig.exe → MI_05 → WinUSB

Full fresh install (includes embeddable Python):
  ./scripts/make_windows_bundle.sh
