feat: Set auth cookie for subdomains

Author: TheMythologist

app/api/auth/callback/route.ts

@@ -84,6 +84,12 @@ export async function GET(req: Request) {
   const in1hour = addHours(new Date(), 1);
 
   cookieStore.set('auth', token, {
+    domain: process.env.NEXT_PUBLIC_VERCEL_PROJECT_PRODUCTION_URL?.replace(
+      'www.',
+      '',
+    ),
+    secure: true,
+    sameSite: 'lax',
     expires: in1hour,
   });