feat: add email settings management

- Introduced EmailSettings component for managing SMTP services.
- Added API endpoints for organization email services including CRUD operations.
- Created database migrations for organization_email_settings and organization_email_services tables.
- Updated the settings page to include EmailSettings component.
- Implemented validation and error handling for email service operations.

services/lms-service/Cargo.toml

@@ -30,3 +30,4 @@ mime_guess = "2.0"
 aws-config = "1"
 aws-sdk-s3 = "1"
 sha2.workspace = true
+lettre = { version = "0.11", default-features = false, features = ["builder", "smtp-transport", "tokio1", "tokio1-native-tls"] }