Split the complex with_advisory_lock function into smaller, focused
functions to improve readability and reduce cyclomatic complexity:
- with_advisory_lock_in_transaction: Handles case when already in transaction
- with_advisory_lock_new_transaction: Handles case when starting new transaction
- execute_within_transaction: Executes function within transaction
- normalize_fun_result: Normalizes function results to consistent format
- handle_transaction_result: Handles transaction results and sends notifications
This fixes Credo warnings:
- Function body nested too deep (was 3, now max 2)
- Function too complex (was 11, now max 9)
- Remove Process.sleep calls from integration tests (tests run synchronously in SQL sandbox)
- Improve error handling: membership_fee_type_not_found now returns changeset error instead of just logging
- Clarify partial_failure documentation: successful_cycles are not persisted on rollback
- Update documentation: joined_at → join_date, left_at → exit_date
- Document PostgreSQL advisory locks per member (not whole table lock)
- Document gap handling: explicitly deleted cycles are not recreated
- Use return_notifications?: true when creating cycles within transaction
- Collect notifications and send them after transaction commits
- Prevents 'Missed notifications' warnings in test output
- Notifications are now properly sent via Ash.Notifier.notify/1
- Change algorithm to start from last existing cycle instead of start_date
- Deleted cycles (gaps) are no longer automatically filled
- Add test to verify gaps remain unfilled
- Update documentation to clarify gap handling behavior
- Handle Task crashes in async_stream with {:exit, reason}
- Return {:error, {:partial_failure, successes, errors}} when some cycles fail
- Previously returned {:ok, successful} even on partial failures
- Improves debuggability and allows callers to handle partial failures
- Remove exit_date filter from generate_cycles_for_all_members query
- Inactive members now get cycles generated up to their exit_date
- Add tests for inactive member processing and exit_date boundary
- Document exit_date == cycle_start behavior (cycle still generated)
