Canteen Management

CanteenDemoSeeder.SeedDietChargeAccrualsAsync -- one DietChargeAccrual per existing demo DietaryOrders row, at that order own diet types DailyRate/BillingCode so the figures agree with the diet-type master a developer can also open. 3 of 4 orders have an identified patient and are marked Posted directly (same end state PostAsync reaches); order 9003 (no patient, per its own existing doc comment) stays Pending, same branch PostAsync takes for a real unidentified admission. Two orders carry a seeded attendant meal count so the Attendant meals KPI shows something besides zero in the demo.