- Added models for NewsletterSystemSettings and NewsletterTemplateSettings to manage configuration.
- Created forms for subscribing and unsubscribing from the newsletter.
- Developed views for handling subscription, confirmation, and unsubscription processes.
- Integrated Member Center API for managing newsletter subscriptions.
- Implemented email sending functionality with SMTP settings.
- Added templates for displaying subscription status and unsubscription confirmation.
- Enhanced CSS for newsletter forms and status messages.
- Included tests for newsletter functionality and security measures for sensitive data.
