feat(installer): J6412 USB installer + AR Electronics license activation server

installer/:
  - build_usb.py: dev tool — builds Flutter + AR-ECDIS, assembles USB pendrive
    image with serial.key, autorun.inf, and START_INSTALLER.bat
  - serial_generator.py: generates AR-XXXX-XXXX-XXXX serial numbers (48-bit
    entropy), logs to CSV for CRM integration
  - src/license.py: hardware fingerprint (Windows MachineGuid + primary MAC),
    serial validation, online activation POST, local cache with 30-day offline
    grace period
  - src/sysconfig.py: HKCU autostart registry entries, .lnk shortcuts (desktop
    + Start Menu via WScript.Shell), firewall rules (netsh), COM port detection
  - src/install.py: tkinter installer GUI — 9 sequential steps with per-step
    progress indicators, threaded execution, error dialogs, and silent mode

license_server/ (FastAPI service — deploy to arelectronics.com VPS):
  - POST /api/v1/activate: first activation accepted; same-HW re-activation
    refreshes heartbeat; different-HW rejected with 409
  - GET  /api/v1/validate/{serial}: heartbeat endpoint to refresh offline cache
  - Admin endpoints (X-Admin-Key): issue, list, revoke licenses
  - SQLAlchemy models: License (serial registry) + Activation (per-machine rows)
  - SQLite default, PostgreSQL-ready via DATABASE_URL env var

AR_electronics — AR-Autopilot Project

license_server/__init__.py

@@ -0,0 +1 @@
+# AR Electronics License Server package