Enhance audience management features with new components and API integrations

- Added `AssignCoursesModal`, `AudienceMemberRow`, `AudienceTable`, and related components for improved audience management UI.
- Implemented audience invite actions including resend and revoke functionality.
- Updated audience API to support importing members and assigning courses.
- Refactored audience data handling to include status and invite management.
- Improved overall user experience with pagination and selection features in the audience table.

apps/dashboard/src/routes/(auth)/signup/+page.svelte

@@ -48,7 +48,7 @@
 
   // Invite context: allow signup when invite_token present or redirect contains invite info
   const hasInviteContext = $derived(
-    !!inviteToken || (!!redirectUrl && (redirectUrl.includes('/invite/t/') || redirectUrl.includes('invite_token')))
+    !!inviteToken || (!!redirectUrl && (redirectUrl.includes('/invite/') || redirectUrl.includes('invite_token')))
   );
 
   const inviteOnly = $derived(!!org?.settings?.signup?.inviteOnly);