- Added gen-secure-msd-sig.sh to sign boot.img with private key using rpi-eeprom-digest
- Added rpi-boot-secure.sh to load signed secure-boot mass storage gadget via rpiboot
- Updated .gitignore to exclude usbboot/ directory
- Updated README with secure boot CM4 unlock instructions
- Added step_set_eth1_mac() to generate and configure random locally administered MAC addresses
- Made --name argument optional and conditional based on selected provisioning steps
- Updated documentation to include MAC configuration in production deployment checklist