feat: implement enrollment audit

[Agrendalath]

Added

• Bulk unenrollment API.
• Enrollment audit model that tracks the enrollment state transitions.
• Allow specifying time commitment.
• Allow duplicating Learning Paths in the Django admin interface.

Changed

• The Learning Paths API includes start and end dates for its steps.
• Return enrollment date in the API instead of a boolean.
• Allow specifying any text for the duration.
• Make the skill level optional.

[Copilot]

Pull Request Overview

This PR implements enrollment audit functionality to record state transitions for learning path enrollments and allowed enrollments. Key changes include the introduction of the LearningPathEnrollmentAudit model and associated audit record creation in signal receivers, modifications in factories and tests to support audit data, and updates to requirements and admin configurations.

Reviewed Changes

Copilot reviewed 25 out of 25 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
requirements/*.txt	Update of common constraints URL and dependency removals
learning_paths/models.py	Addition of the enrollment audit model
learning_paths/receivers.py	Enhancement of signal receivers to create audit records
learning_paths/tests/*	New and updated tests to verify audit record creation
learning_paths/api/v1/views.py	Bulk enrollment API now sets audit data for both enrollments and allowed enrollments
learning_paths/admin.py	New inline admin configurations for viewing audit records
migrations/*	Database migration for the audit model and removal of historical models

[Copilot]

Pull Request Overview

This PR implements an enrollment audit feature to track state transitions during learner enrollment and unenrollment, and extends bulk enrollment/unenrollment API endpoints to support audit logging. Key changes include updates to requirements files for common constraints, creation of a new LearningPathEnrollmentAudit model with supporting tests and admin inlines, and modifications to signal receivers and API views to create audit records.

Reviewed Changes

Copilot reviewed 26 out of 26 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
requirements/*	Updated constraint references and removed legacy django-simple-history pinning
learning_paths/models.py	Introduced LearningPathEnrollmentAudit model and updated related models
learning_paths/receivers.py	Added signal receivers and helper functions for audit record creation
learning_paths/api/v1/views.py	Extended bulk enroll/unenroll API endpoints to incorporate audit logging
learning_paths/tests/*	Added extensive tests to validate enrollment audit functionality
learning_paths/admin.py	Configured new admin inlines and admin registration for audit models
Makefile, CHANGELOG.rst, .github/workflows/ci.yml	Updated build and versioning files reflecting the new feature

Comments suppressed due to low confidence (1)

learning_paths/api/v1/views.py:392

• Consider using django.utils.timezone.now() instead of datetime.now(timezone.utc) to maintain consistency with Django's timezone handling throughout the project.

enrollment.enrolled_at = datetime.now(timezone.utc)

[Agrendalath]

Merging to unblock the certificate criteria work.