Revert "fix: add fair queueing for celery"

[thomasrockhu-codecov]

Reverts #780

---

Note

Low Risk
Low risk revert that only changes the Celery worker CLI options; behavior change is limited to task scheduling fairness/performance characteristics.

Overview
Reverts the previous change that enabled Celery fair queueing by dropping the -Ofair flag from the worker argv in apps/worker/main.py.

Updates the worker CLI unit tests to match the new argument list (no fair-queueing option).

^{Written by Cursor Bugbot for commit 6ceb08b. This will update automatically on new commits. Configure here.}

[sentry]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 92.25%. Comparing base (857b3db) to head (6ceb08b).
✅ All tests successful. No failed tests found.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #781   +/-   ##
=======================================
  Coverage   92.25%   92.25%           
=======================================
  Files        1305     1305           
  Lines       47981    47981           
  Branches     1636     1636           
=======================================
  Hits        44263    44263           
  Misses       3407     3407           
  Partials      311      311           

Flag	Coverage Δ
workerintegration	58.56% <ø> (ø)
workerunit	90.38% <ø> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

[codecov-notifications]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ All tests successful. No failed tests found.

📢 Thoughts on this report? Let us know!