## [0.16.0] - 2026-02-XX

### Added
- Optional asynchronous invoice posting mode (`ASYNC_OUTBOX`)
- Invoice lifecycle states to track accounting system synchronization
- Support for deferred posting to external accounting systems

### Changed
- `issueInvoice()` now supports an opt-in asynchronous posting mode
- Accounting system integration can be executed outside database transactions

### Backward Compatibility
- Default behavior remains synchronous (`SYNC_LEGACY`)
- Existing consumers are not affected unless explicitly opted in

### Notes
- Synchronous posting mode will be deprecated in a future `1.0.0` release