feat(ui): polish domains UX and dark-mode loading accents

Group service domain tables with inline redirect controls, live-save
redirects without full refreshes, and only auto-pair www hosts when a
www redirect is active. Align helper tooltips, server-timing HUD, and
loading spinners with dark-theme accents; default theme-color to dark.

tests/Feature/DefaultThemeTest.php

@@ -0,0 +1,11 @@
+<?php
+
+test('new users default to dark mode', function () {
+    $layout = file_get_contents(resource_path('views/layouts/base.blade.php'));
+
+    expect($layout)
+        ->toContain('<html data-theme="dark"')
+        ->toContain("const t = localStorage.theme || 'dark';")
+        ->toContain("localStorage.theme = 'dark';")
+        ->toContain('<meta name="theme-color" content="#101010" id="theme-color-meta" />');
+});