feat: add custom site name

src/app/layout.tsx

@@ -8,7 +8,7 @@ import { ThemeProvider } from '../components/ThemeProvider';
 const inter = Inter({ subsets: ['latin'] });
 
 export const metadata: Metadata = {
-  title: 'MoonTV',
+  title: process.env.NEXT_PUBLIC_SITE_NAME || 'MoonTV',
   description: '影视聚合',
   manifest: '/manifest.json',
 };