- Redesigned all email templates with professional corporate style
- Created base layout with dark header, status cards, and footer
- Updated: subscription-cancelled, account-activation, welcome, welcome-new-user, due-payments-alert
- Removed emojis and gradients for cleaner look
- Added multi-language support (ES, PT-BR, EN)
- Fixed email delivery (sync instead of queue)
- Fixed PayPal already-cancelled subscription handling
- Cleaned orphan subscriptions from deleted users
- Criar tabela plans com Free, Pro Monthly, Pro Annual
- Criar tabela subscriptions com status e integração PayPal
- Criar tabela invoices com numeração sequencial WM-YYYY-NNNNNN
- Models: Plan, Subscription, Invoice com helpers
- User: hasActiveSubscription(), onTrial(), currentPlan(), etc.
- API: GET /api/plans (público)
- Seeder: PlansSeeder com 3 planos base
- Fase 2 do roadmap SaaS concluída
