9.1
billing: Remove success message from URL after being displayed.
remote_billing: Add endpoint and a helper to make deactivation links.
stripe: Fix $0 invoices being generated on upgrade.
web: Qualify global uses of location and history.
page_params: Parse page_params and state_data with Zod.
billing/remote_billing_auth: Fix TypeScript noUncheckedIndexedAccess errors.
support: Set discounted price instead percentage for customers.