Add admin site settings sections and locale defaults

tests/metadata.test.ts

@@ -17,6 +17,8 @@ describe("metadata helpers", () => {
 
   it("builds root metadata with dynamic icons and social preview", () => {
     const settings = buildDefaultSiteSettings("Studio Moh");
+    settings.defaultLocale = "ar";
+    settings.locales.ar.siteName = "Studio Moh AR";
     const metadata = buildAppMetadataFromConfig(settings, {
       siteLogoLight: null,
       siteLogoDark: null,
@@ -32,12 +34,16 @@ describe("metadata helpers", () => {
       },
     });
 
-    expect(metadata.title).toBe("Studio Moh");
+    expect(metadata.title).toBe("Studio Moh AR");
     expect(metadata.icons).toEqual({
       icon: [{ url: "/favicon.ico?v=v1" }],
       shortcut: [{ url: "/favicon.ico?v=v1" }],
       apple: [{ url: "/apple-icon.png?v=v1" }],
     });
+    expect(metadata.openGraph).toMatchObject({
+      locale: "ar",
+      url: "https://mohfarawati.de/",
+    });
     expect(metadata.twitter).toMatchObject({
       card: "summary_large_image",
     });