feat(server): fall back Sentinel URL to request host

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.

tests/Feature/ServerIndexViewSwitcherTest.php

@@ -20,3 +20,13 @@ test('view switchers use the shared coollabs selected state on every page', func
         ->toContain('@utility control-selected')
         ->toContain('@apply bg-coollabs text-white dark:bg-coollabs dark:text-white;');
 });
+
+test('server index does not expose server IP addresses', function () {
+    $view = file_get_contents(resource_path('views/livewire/server/index.blade.php'));
+
+    expect($view)
+        ->not->toContain("'address' => \$server->ip")
+        ->not->toContain('<div>Address</div>')
+        ->not->toContain('x-text="server.address"')
+        ->not->toContain('server.address,');
+});