fix(teams): disable submit button for single-member teams

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Co-Authored-By: Claude <noreply@anthropic.com>

apps/hackathon/src/app/teams/[teamId]/page.tsx

@@ -429,7 +429,7 @@ const TeamDashboardPage: FC = (): ReactElement => {
                     </Link>
                   ) : (
                     <Link to={`/teams/${teamId}/submit`}>
-                      <Button className="w-full">
+                      <Button className="w-full" disabled={members.length < 2}>
                         <Icon icon="mdi:rocket" className="inline-block mr-2" />
                         Submit Project
                       </Button>