Remove redundant NEXT_PUBLIC_BASE_URL as it's unused
Add baseUrl() utility function that prioritizes VERCEL_URL over BASE_URL
Update Stripe checkout and portal URLs to use baseUrl()
Simplify setup script to only set BASE_URL for local development
This change ensures consistent URL handling across environments, with
Vercel deployments automatically using the correct URL and local development
falling back to BASE_URL.
This change ensures consistent URL handling across environments, with Vercel deployments automatically using the correct URL and local development falling back to BASE_URL.