feat: unified launcher, multi-OS hardening, login alerts & auto-updates

Restructure around a single entry point (automations.sh) with a Gum wizard and
a self-extracting bundle for repo-less installs. Add scripts/oslib.sh so the
provisioning scripts (setup-host, harden-ssh, harden-jumphost, sshuser) run on
Alpine/Debian/Alma; seed root keys from globals/.

- ntfy SSH-login alerts (user, source IP, key, region, jump target) via pam_exec
- daily auto-updates with AUTO_REBOOT=idle (reboots only when no SSH active) and
  opt-in Alpine stable-branch upgrades
- generic + per-deployment cloud-init; Gitea release workflow on tag
- README/LICENSE/.gitignore/.gitattributes (force LF); repo URLs -> Gitea

deployments/beszel/.env.example

@@ -0,0 +1,17 @@
+# Copy to .env and fill in. docker compose picks .env up automatically.
+
+# ─── Public hostname ────────────────────────────────────────────────────────
+# Bare hostname (no scheme) where beszel will be reached.
+BESZEL_DOMAIN=monitoring.example.com
+
+# Email for Let's Encrypt registration / expiry notifications.
+ACME_EMAIL=admin@example.com
+
+# Allow OIDC sign-in to auto-create user accounts on first login. Set to
+# "false" if you want to manually pre-create users in the admin UI before
+# anyone can log in.
+USER_CREATION=true
+
+# ─── Image tags ─────────────────────────────────────────────────────────────
+BESZEL_TAG=latest
+CADDY_TAG=2-alpine