JWT Token Expires Silently Causing Unexpected Logout

1. autoRefreshToken not enabled in Supabase client config
2. No error handling for expired token (401 response)
3. Refresh token also expired or missing
4. App doesn't check token expiration before making requests
5. Network request fails during token refresh

Enable automatic token refresh and add auth state listener:

const { data: { session } } = await supabase.auth.getSession();

supabase.auth.onAuthStateChange((event, session) => {
  if (event === 'TOKEN_REFRESHED') {
    console.log('Token refreshed');
  } else if (event === 'SIGNED_OUT') {
    // Redirect to login
  }
});