fix(settings): drop the back-link on Appearance subpages

The "back to Appearance" link above the heading on each /settings/layout/
<module> subpage pushed the whole section down and read as clutter. Remove
it — the subpage is a dead end reached from the hub or the module cog; the
left nav already returns to Appearance. The shared back-link primitive
stays (still used by the shell's layout-child fallback path).

src/app/settings/layout/[module]/page.tsx

@@ -6,7 +6,6 @@ import {
   LAYOUT_GROUP_IDS,
   isLayoutGroupId,
 } from "@/components/settings/layout-groups";
-import { SettingsHubBackLink } from "@/components/settings/settings-hub-back-link";
 import { SettingsShell } from "@/components/settings/settings-shell";
 import { resolveServerLocale } from "@/lib/i18n/server-locale";
 import { getServerTranslator } from "@/lib/i18n/server-translator";
@@ -67,12 +66,6 @@ export default async function SettingsLayoutModulePage({ params }: PageProps) {
         title: t(group.titleKey),
         subtitle: t(group.descriptionKey),
         headingId,
-        topSlot: (
-          <SettingsHubBackLink
-            href="/settings/layout"
-            labelKey="settings.sections.layout.backToHub"
-          />
-        ),
       }}
     >
       <section aria-labelledby={headingId} className="space-y-6">