- Update cache expiration times for `economicCustomerName` and `isBooked` objects
- Introduce `getCachedForMultipleObjects` for batch cache retrieval
- Optimize `isBooked` with optional caching and update to store results
- Implement `getCustomerNames` in `users_o` with caching for bulk name retrieval
- Refactor customer transaction handling in `InvoicingPeriodRoute` for efficiency
- Filter orders excluded from invoicing in `collected_order_invoices_o`