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/ServerCreatePageLayoutTest.php

@@ -5,6 +5,16 @@ test('server creation uses the standard page title without redundant navigation'
 
     expect($view)
         ->toContain('<h1 class="min-w-0 text-[24px]! leading-7! font-semibold! tracking-tight!">New server</h1>')
+        ->toContain('class="mb-5 flex min-h-9 flex-col gap-3 sm:flex-row sm:items-center sm:justify-between"')
         ->not->toContain('Back to servers')
         ->not->toContain('title="Add a server"');
 });
+
+test('provider pages only show the token action in the account panel', function () {
+    $view = file_get_contents(resource_path('views/livewire/server/create.blade.php'));
+
+    expect($view)
+        ->not->toContain('New token')
+        ->not->toContain('new-server-token-')
+        ->not->toContain('tokenProviderName');
+});