Canteen Management

End-of-day reconciliation that a person signs for.

• Close per outlet, reconciled per counter and cashier against the cash actually counted.
• A variance needs a note; a close is idempotent and returns the existing close when repeated.
• Blocked while any sale is awaiting payment or has a void request pending.
• Stamps every sale of that outlet and day; stamped sales cannot be changed and a new sale on that outlet and day is refused.
• A day lock stops a sale completing between the close's totals and its stamp.
• Journal CSV rebuilt from the stamped sales: sales by GST rate, staff subsidy, cash counted, cash short or over.
• Needs the canteen.day_close.execute permission.

Built and tested on integration/canteen-v1; merge to dev pending.