Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Covers encryption (age key management), what is protected, backup command, daily cron, preflight checks, full step-by-step restore procedure, restore drill instructions, and two extension points (EP-RAIL-003 git mirrors, EP-RAIL-004 offsite secondary copy). Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>