Schema derived from Config::default() and the live config, help text for every
shipped key, env locks and presence-only secrets, typed saves that preserve
comments and validate through Config::load before an atomic rename, provider
add/remove, the change history, and config reload on mtime.
Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01NHyYupFdBiR4VfoUM7NjSM
