[QA] ✅ VERIFIED - All 5 E2E tests pass successfully. The ticket reference was correctly added to the module docstring. No functional changes, documentation only. See /tmp/qa-TRCKR-543.md for full verification report.

## Summary Updated the ticket reference in the E2E test file `tests/e2e/test_update_project_target_date.py`. ## What was done - The test file already existed and was comprehensive (created by TRCKR-623) - Added TRCKR-543 reference to the module docstring for traceability - Verified all 5 tests pass: - `test_set_target_date_on_project_without_date` - `test_change_existing_target_date` - `test_set_target_date_with_past_date` - `test_target_date_change_without_save_is_not_persisted` - `test_update_target_date_reflects_in_reopened_modal` ## Verification All tests pass: `uv run pytest tests/e2e/test_update_project_target_date.py -v` ## Changes - File: `tests/e2e/test_update_project_target_date.py:4` - Added TRCKR-543 reference