Introduce InventoryHistoryConfig.RetentionRowsPerViewer as the single
source of truth for the 300-row audit-log cap; InventoryTransaction
aliases it and ItemAcquireHistoryController.Take() references it
directly so the two sites cannot drift. Also adds CultureInfo.InvariantCulture
to the AcquireTime.ToString() call, matching every other WireDateFormat
site in the codebase.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Add ItemAcquireHistoryController (POST /item_acquire_history/info) with its
three DTOs and two integration tests (ordering + empty-viewer). The endpoint
reads ViewerAcquireHistory rows written by InventoryTransaction.CommitAsync,
ordered newest-first, capped at 300. Tests access doc.RootElement.histories
directly (no envelope wrapper in the test path — middleware skips non-UnityPlayer UA).
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
