fix: use next_public_app_url for share link base url instead of localhost fallback

src/modules/_core/share.ts

@@ -20,7 +20,8 @@ function hashToken(raw: string): string {
 }
 
 function buildUrl(token: string): string {
-  const base = process.env["NEXTAUTH_URL"] ?? "http://localhost:3000";
+  const base =
+    process.env["NEXT_PUBLIC_APP_URL"] ?? process.env["AUTH_URL"] ?? "http://localhost:3000";
   return `${base}/s/${token}`;
 }