Unify Certificate Generation and Regeneration APIs into a Single Endpoint

These apis can be converted into one single api.

Currently, we have three separate API endpoints for initiating certificate-related tasks:

https://github.com/openedx/edx-platform/blob/8fac3bc060ca7c79dce33117903b715841d4385f/lms/djangoapps/instructor/views/api_urls.py#L84

enable_certificate_generation - enables or disables self-generated certificates for students.
start_certificate_generation – starts generation for all enrolled students.
start_certificate_regeneration – regenerates certificates based on provided certificate_statuses.

All endpoints perform similar operations (triggering background tasks for a course), but differ slightly in required input and logic. To simplify API usage, reduce duplication, and improve maintainability, we propose merging both endpoints into a single unified API.

Proposed Changes:

Introduce a unified API endpoint:
/certificate_task/<course_id>

Use a mode parameter in POST data to determine the action:

generate
regenerate
toggle


You'll also need to update the frontend code to replace all usages of the old endpoints with the new unified API.