- Updated `MailingsController` with new endpoints for name availability and next available name.
- Modified existing methods to accept optional date parameters.
- Introduced `TestMailingDto` for testing mailings with email addresses.
- Updated `IMailingRepository` and `IMailingService` interfaces for new methods.
- Enhanced `MailingRepository` and `MailingService` to support new logic for testing and sending emails.
- Updated `appsettings.json` with new SendGrid settings and default unsubscribe URL.
- Modified `MailingEdit` component to fetch next available name and handle test mailings.
- Added search filters for start and end dates in `CompletedMailings` component.
- Included `react-toastify` for notifications in `package.json` and `package-lock.json`.
- Updated `App` component to include `ToastContainer` for displaying notifications.
David Headrick
26abe9e028