fix(ui): polish mobile layouts, error pages, and volume backups

Keep error pages full-viewport, lift the unsaved bar above the
mobile keyboard, make status/heading layouts stack cleanly on small
screens, route service DB backups to volume-backups, and tighten
volume backup grid/forms. Cover with feature tests.

resources/views/livewire/project/application/general.blade.php

@@ -49,7 +49,7 @@
                     $domainCount = countDomains($fqdn);
                 }
             @endphp
-            <div class="flex flex-col gap-3 rounded-lg border border-neutral-200 bg-neutral-50/60 px-4 py-3 sm:flex-row sm:items-center dark:border-white/[0.07] dark:bg-white/[0.025]">
+            <div class="flex items-center gap-3 rounded-lg border border-neutral-200 bg-neutral-50/60 px-4 py-3 dark:border-white/[0.07] dark:bg-white/[0.025]">
                 <div class="flex min-w-0 flex-1 items-center gap-3">
                     <div class="flex size-9 shrink-0 items-center justify-center rounded-md bg-neutral-200/70 text-neutral-600 dark:bg-white/[0.07] dark:text-fg-dim">
                         <x-reicon name="globe" class="size-4" />
@@ -63,7 +63,7 @@
                         </p>
                     </div>
                 </div>
-                <a class="icon-button shrink-0 self-start sm:self-auto" title="Manage domains"
+                <a class="icon-button ml-auto shrink-0" title="Manage domains"
                     aria-label="Manage domains"
                     href="{{ route('project.application.domains', [
                         'project_uuid' => $application->environment->project->uuid,