- Modified test data in template tests to include 'invitation_link' and 'expires_at' fields, ensuring alignment with the actual template structure.
- Changed message type verification from "mail" to "email" for clarity and accuracy.
- Enhanced comments for better understanding of test data relevance.
- Introduced template loading functionality during messenger initialization, allowing for dynamic message templates.
- Added SendT, SendTWithProvider, SendTBatch, and SendTBatchMixed methods to the Service for sending messages using templates.
- Updated provider implementations for Mailgun, Twilio, and Mailer to support template-based message sending.
- Enhanced the Provider interface to include optional template methods, improving flexibility and usability across providers.
