add login/sign-up page with dark/light mode

node_modules/next/dist/client/components/is-next-router-error.d.ts

@@ -0,0 +1,8 @@
+import { type HTTPAccessFallbackError } from './http-access-fallback/http-access-fallback';
+import { type RedirectError } from './redirect-error';
+/**
+ * Returns true if the error is a navigation signal error. These errors are
+ * thrown by user code to perform navigation operations and interrupt the React
+ * render.
+ */
+export declare function isNextRouterError(error: unknown): error is RedirectError | HTTPAccessFallbackError;