feat: add Runtipi addon + upgrade all addons with Proxmox host check, optional Docker install, Alpine support

- New: tools/addon/runtipi.sh with full Alpine support (gcompat for musl)
- New: tools/headers/runtipi ASCII header
- Updated: runtipi.json to addon type with null resources
- Removed: ct/runtipi.sh, install/runtipi-install.sh (migrated to addon)
- All addons (dockge, komodo, dokploy, coolify, runtipi) now have:
  - check_proxmox_host(): warns when running on PVE host, default N
  - check_or_install_docker(): optional Docker install (Debian+Alpine)
  - Alpine-aware curl bootstrap and dependency installation

tools/headers/runtipi

@@ -0,0 +1,5 @@
+    ____              __  _      _
+   / __ \__  ______  / /_(_)__  (_)
+  / /_/ / / / / __ \/ __/ / _ \/ /
+ / _, _/ /_/ / / / / /_/ / ___/ /
+/_/ |_|\__,_/_/ /_/\__/_/_/  /_/