Add new services and endpoints for payplug.

PayPlug Integration

This MR implements the integration of PayPlug as a payment method. It includes:

Features

• DTO Creation

  • Creation of DTOs for request and response to standardize data exchanges.

• Service Methods

  • Implementation of service methods that communicate with the PayPlug microservice to handle payment operations and configuration of API keys an payplug mode (Test / Live).

• New Endpoint

  • Addition of a new endpoint in the controller to:
    • Process payment requests via PayPlug.
    • Return responses to mydressin-front or mydressin-client.