Add promotion route

[thanthtooaung-coding]

Description:

The implementation for promotion-related routes has been completed in the feature/promotion-routes branch. This includes basic CRUD operations and related API endpoints.

Details:

• All promotion-related endpoints are fully functional.
• Routes include:
  • Create Promotion
  • Get all Promotions
  • Get Promotion by ID
  • Update Promotion
  • Delete Promotion

Next Steps:

• Review the code in the feature/promotion-routes branch.
• Ensure the following are completed:
  • Code meets coding standards and guidelines.
  • Endpoints are tested thoroughly for functionality and edge cases.
  • API documentation is updated for all promotion routes.

Acceptance Criteria:

1. Routes are reviewed and meet quality standards.
2. All test cases pass.
3. Documentation is complete and clear.