Extract a shared forms collapsible for advanced SSH/build settings
across boarding, server creation, and application general. Support
larger modals with header actions, close the compose editor after
save via compose-save-finished, and cover the layout in tests.
Use the current request scheme/host when no FQDN or public IP is set,
skipping loopback hosts. Polish boarding/server create cards, optional
listbox tooltips, and cover the layout and Sentinel URL behavior in tests.
Ensure a Sentinel endpoint from instance FQDN/IP when enabling, use process dialogs for validation with install state, and tidy server create, boarding, metrics empty state, and log timestamps.
