- Add monthly/annual billing toggle with 25% annual discount on pricing page
- Implement 14-day no-card free trial (server-side Stripe subscription creation)
- Enable upgrade/downgrade via Stripe Customer Portal
- Add admin-initiated ACH/invoice billing for enterprise customers
- Add billing card to Settings page with plan info and Manage Billing button
- Handle past_due status with read-only grace period access
- Add trial ending and trial expired email templates
- Add DB migration for billing_interval and collection_method columns
- Update ONBOARDING-AND-AUTH.md documentation
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Covers Stripe billing flow, provisioning pipeline, activation magic links,
onboarding checklist, refresh tokens, MFA, SSO, passkeys, env var reference,
manual intervention checklist, and full API endpoint reference.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
