feat: guest information form enter details

lib/discriminatedUnion.ts

@@ -21,7 +21,7 @@ import type {
  * is an Interface e.g).
  */
 
-export function discriminatedUnion<T extends Option>(options: T[]) {
+export function discriminatedUnion<R>(options: Option[]) {
   return z
     .discriminatedUnion("__typename", [
       z.object({ __typename: z.literal(undefined) }),
@@ -37,6 +37,12 @@ export function discriminatedUnion<T extends Option>(options: T[]) {
       }
       throw new Error(error.message)
     })
+    .transform((data) => {
+      if (data.__typename === "undefined" || data.__typename === undefined) {
+        return null
+      }
+      return data as R
+    })
 }
 
 export function discriminatedUnionArray<T extends Option>(options: T[]) {