fix(frontend): waitlist modal copy (#11263)

### Changes 🏗️

### Before

<img width="800" height="649" alt="Screenshot_2025-10-23_at_00 44 59"
src="https://github.com/user-attachments/assets/fd717d39-772a-4331-bc54-4db15a9a3107"
/>

### After

<img width="800" height="555" alt="Screenshot 2025-10-27 at 23 19 10"
src="https://github.com/user-attachments/assets/64878bd0-3a96-4b3a-8344-1a88c89de52e"
/>

### Checklist 📋

#### For code changes:
- [x] I have clearly listed my changes in the PR description
- [x] I have made a test plan
- [x] I have tested my changes according to the test plan:
  - [x] Try to signup with a non-approved email
  - [x] You see the modal with an updated copy

autogpt_platform/frontend/src/app/(platform)/auth/auth-code-error/page.tsx

@@ -44,10 +44,7 @@ export default function AuthErrorPage() {
     return (
       <div className="flex h-screen items-center justify-center">
         <Card className="w-full max-w-md p-8">
-          <WaitlistErrorContent
-            onClose={() => router.push("/login")}
-            closeButtonText="Back to Login"
-          />
+          <WaitlistErrorContent onBackToLogin={() => router.push("/login")} />
         </Card>
       </div>
     );

autogpt_platform/frontend/src/components/auth/EmailNotAllowedModal.tsx

@@ -14,7 +14,7 @@ export function EmailNotAllowedModal({ isOpen, onClose }: Props) {
     >
       <Dialog.Content>
         <div className="py-4">
-          <WaitlistErrorContent onClose={onClose} />
+          <WaitlistErrorContent />
         </div>
       </Dialog.Content>
     </Dialog>

autogpt_platform/frontend/src/components/auth/WaitlistErrorContent.tsx

@@ -1,50 +1,39 @@
 import { Button } from "../atoms/Button/Button";
 import { Text } from "../atoms/Text/Text";
 
-interface WaitlistErrorContentProps {
-  onClose: () => void;
-  closeButtonText?: string;
-  closeButtonVariant?: "primary" | "secondary";
+interface Props {
+  onBackToLogin?: () => void;
 }
 
-export function WaitlistErrorContent({
-  onClose,
-  closeButtonText = "Close",
-  closeButtonVariant = "primary",
-}: WaitlistErrorContentProps) {
+export function WaitlistErrorContent(props: Props) {
   return (
     <div className="flex flex-col items-center gap-6">
-      <Text variant="h3">Join the Waitlist</Text>
+      <Text variant="h3">We&apos;re in closed beta</Text>
       <div className="flex flex-col gap-4 text-center">
-        <Text variant="large-medium" className="text-center">
-          The AutoGPT Platform is currently in closed beta. Your email address
-          isn&apos;t on our current allowlist for early access.
-        </Text>
-        <Text variant="body" className="text-center">
-          Join our waitlist to get notified when we open up access!
+        <Text variant="large" className="text-center">
+          Looks like your email isn&apos;t in our early access list just yet.
+          Join the waitlist and we will let you know the moment we open up
+          access!
         </Text>
       </div>
-      <div className="flex gap-3">
+      <div className="flex gap-2">
         <Button
-          variant="secondary"
           onClick={() => {
             window.open("https://agpt.co/waitlist", "_blank");
           }}
         >
           Join Waitlist
         </Button>
-        <Button variant={closeButtonVariant} onClick={onClose}>
-          {closeButtonText}
-        </Button>
+        {props.onBackToLogin ? (
+          <Button variant="secondary" onClick={props.onBackToLogin}>
+            Back to Login
+          </Button>
+        ) : null}
       </div>
       <div className="flex flex-col gap-2">
         <Text variant="small" className="text-center text-muted-foreground">
-          Already signed up for the waitlist? Make sure you&apos;re using the
-          exact same email address you used when signing up.
-        </Text>
-        <Text variant="small" className="text-center text-muted-foreground">
-          If you&apos;re not sure which email you used or need help, contact us
-          at{" "}
+          Already joined? Double-check you are using the same email you signed
+          up with. Need a hand? Emails us at{" "}
           <a
             href="mailto:contact@agpt.co"
             className="underline hover:text-foreground"
@@ -58,7 +47,7 @@ export function WaitlistErrorContent({
             rel="noopener noreferrer"
             className="underline hover:text-foreground"
           >
-            reach out on Discord
+            message us on Discord
           </a>
         </Text>
       </div>