Update and maintain OpenAPI schema

[lunika]

Feature Request

Is your feature request related to a problem or unsupported use case? Please describe.

Our OpenAPI schema is not accurate, we rely only on what is provided by DRF. It brings basic information but they are incomplete. With a complete and valid OpenAPI schema, the front can use it to maintain its types with library like orval

Describe the solution you'd like

The schema can be extended using the decorator @extend_schema.