STIG: Display the DoD Notice and Consent Banner

Federal systems must display the Standard Mandatory DoD Notice and Consent Banner before granting access (UBTU-22-255020). The approved text is on this box at /root/case/dod-banner.txt. Put it in /etc/issue (console logins) and /etc/issue.net (network logins), and point sshd at /etc/issue.net with the Banner directive. A generic 'authorized use only' line is not enough: the STIG check compares the full text. Line wrapping can differ; the words and punctuation can't.