chore: refactor LCR bulk actions to align with Content Assignments

[zwidekalanga]

Description:
Refactor LCR bulk actions to align with Content Assignments as bulk action in frontend should behave identically.

Jira:
ENT-11480

Merge checklist:

• ./manage.py makemigrations has been run
  • Note: This must be run if you modified any models.
    • It may or may not make a migration depending on exactly what you modified, but it should still be run.

Post merge:

• Ensure that your changes went out to the stage instance
• Deploy to prod instance

[codecov]

Codecov Report

❌ Patch coverage is 79.71014% with 14 lines in your changes missing coverage. Please review.
✅ Project coverage is 84.20%. Comparing base (dfdeddf) to head (d958f33).
⚠️ Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
...ise_access/apps/api/v1/views/browse_and_request.py	64.86%	10 Missing and 3 partials ⚠️
enterprise_access/apps/subsidy_request/api.py	96.29%	0 Missing and 1 partial ⚠️

❌ Your patch status has failed because the patch coverage (79.71%) is below the target coverage (95.00%). You can increase the patch coverage or adjust the target coverage.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #100      +/-   ##
==========================================
+ Coverage   84.01%   84.20%   +0.18%     
==========================================
  Files         144      144              
  Lines       12226    12128      -98     
  Branches     1170     1155      -15     
==========================================
- Hits        10272    10212      -60     
+ Misses       1625     1596      -29     
+ Partials      329      320       -9     

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[Copilot]

Pull request overview

Refactors Learner Credit Request (LCR) bulk action behavior to mirror Content Assignments patterns, centralizing bulk logic in subsidy_request.api and updating the B&R v1 endpoints/serializers accordingly.

Changes:

• Added state-group constants (APPROVABLE_STATES, DECLINABLE_STATES, REMINDABLE_STATES) and updated API/view filtering to use them.
• Introduced decline_learner_credit_requests API and refactored remind/decline flows to use bulk action/audit creation patterns.
• Updated DRF serializers/endpoints and expanded/adjusted test coverage for the new decline-all and API-layer behavior.

Reviewed changes

Copilot reviewed 8 out of 8 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
enterprise_access/apps/subsidy_request/tests/test_api.py	Adds API-layer tests for approve/remind/cancel/decline bulk behaviors.
enterprise_access/apps/subsidy_request/models.py	Removes unused bulk approve helper; keeps bulk decline behavior in model.
enterprise_access/apps/subsidy_request/constants.py	Adds state-group constants to standardize bulk operation filtering.
enterprise_access/apps/subsidy_request/api.py	Refactors bulk approve/remind and adds bulk decline API with audit/task behavior.
enterprise_access/apps/api/v1/views/browse_and_request.py	Updates LCR endpoints: approve-all response body, decline (single) refactor, adds decline-all.
enterprise_access/apps/api/v1/tests/test_browse_and_request_views.py	Updates view tests to match new decline-all/decline behaviors and routes.
enterprise_access/apps/api/serializers/subsidy_requests.py	Adds decline-all serializer; makes remind require UUID list (removes legacy single UUID support).
enterprise_access/apps/api/serializers/init.py	Exposes new serializer; removes bulk approve/decline serializers.

Comments suppressed due to low confidence (1)

enterprise_access/apps/subsidy_request/api.py:54

• approve_learner_credit_requests returns {"approved": [], "failed": ...} when there are no approvable requests (line 53), but returns failed_approval in the normal path (line 122). This inconsistent contract can cause callers to silently miss failures (e.g., views that only read failed_approval). Consider standardizing on a single key (e.g., always failed_approval) across all return paths and updating callers/tests accordingly.

    requests_to_process = [
        req for req in learner_credit_requests
        if req.state in APPROVABLE_STATES
    ]
    if not requests_to_process:
        return {"approved": [], "failed": list(learner_credit_requests)}

[iloveagent57]

approved to unblock, but this change is worth making: #100 (comment)