Adds a deploy wrapper around `clan machines update` that:
- Syncs the password store (pull/push) around deploys
- Extracts the bulk age key into a secure tmpdir for fast decryption
- Cleans up key material on exit

Co-Authored-By: Claude (claude-opus-4-6) <noreply@anthropic.com>

Add usage.kdl (https://usage.jdx.dev/spec/) files for all 32 tools
describing their CLI interface. Each tool exposes its spec as a string
via passthru.usage (builtins.readFile ./usage.kdl).

The s wrapper now includes a zsh completion function that:
- Instantly completes package names (baked in at build time)
- Lazily fetches per-tool usage specs via nix eval on first use
- Caches specs keyed by flake narHash for invalidation

- systemd service running as dedicated kanban user on SSD (zroot)
- nginx reverse proxy at kanban.lassul.us with basic auth via clan vars
- DNS record for kanban.lassul.us
- binary-patch claude-code version for claude 4.6 support
- backup of vibe-kanban state

nixos-mailserver mkForces the virtualMail user without homeMode,
causing NixOS activation to reset /var/vmail to 0700 on every deploy.
Override at the same priority to set homeMode=2770, replacing the
chmod workaround in ExecStartPost.

SnappyMail PHP webmail served via nginx + php-fpm.
Data stored in /var/lib/snappymail.
Admin panel at mail.lassul.us/?admin after first deploy.