Add email logging and SMTP health check

- Add structured logging for email sending (success/failure)
- Add HealthCheck method to EmailService interface
- Extend /health endpoint to include SMTP status
- Update all email service mocks to implement HealthCheck
- SMTP status shows: ok, error, or disabled

internal/application/commands/request_password_reset_test.go

@@ -85,6 +85,10 @@ func (m *mockRequestResetEmailService) Send(message services.EmailMessage) error
 	return nil
 }
 
+func (m *mockRequestResetEmailService) HealthCheck() error {
+	return nil
+}
+
 func TestRequestPasswordResetHandler_Success(t *testing.T) {
 	user := entities.NewUser("test@example.com", "hash")
 	user.ID = "user-123"