guimaraf/misterFPGA-Scripts-by-Fred — reverse-engineered prompt

Build me a small pack of easy MiSTer FPGA utility scripts that I can copy into /media/fat/Scripts and run from the MiSTer Scripts menu or terminal.

I want simple shell scripts to check the current vsync_adjust value in /media/fat/MiSTer.ini, switch it to 0, 1, or 2, and always make a backup before changing anything. Add a safe power off script with a visible countdown that can be cancelled by pressing any controller button. Add a time sync script that updates the system date and time from multiple internet time servers, even if there is no RTC board.

Also include scripts to swap the main MiSTer file between my Original backup and my RetroArchiviements backup, then reboot. Add a checker that tells me which main file seems installed. Finally, add simple scripts to restore update_senhor.sh from GitHub and patch its internet check, with backups.

Please make the scripts clear, safe, and include a short README in English and Brazilian Portuguese.