refactor: simplify order status model — remove DELIVERY_FEE_ADJUSTMENT and PAYMENT_VERIFICATION

- Add deliveryFeeLocked field to Order model
- Remove DELIVERY_FEE_ADJUSTMENT and PAYMENT_VERIFICATION statuses (11→8)
- 3 order paths: delivery+online (locked→unlocked→paid), pickup+online (unlocked→paid), pickup+on_pickup (direct to in_progress)
- Update checkout to use PENDING_PAYMENT + deliveryFeeLocked
- Update payment flow to stay in PENDING_PAYMENT until admin confirms
- Update admin UI to use deliveryFeeLocked instead of status check
- Update client payment UI with new deliveryFeeLocked logic

server/src/lib/__tests__/order-status.test.js

@@ -17,6 +17,14 @@ describe('canTransitionAdminOrderStatus', () => {
     expect(canTransitionAdminOrderStatus({ status: 'DRAFT', ...delivery }, 'PAID')).toBe(false)
   })
 
+  it('PENDING_PAYMENT → PAID', () => {
+    expect(canTransitionAdminOrderStatus({ status: 'PENDING_PAYMENT', ...delivery }, 'PAID')).toBe(true)
+  })
+
+  it('PENDING_PAYMENT → CANCELLED', () => {
+    expect(canTransitionAdminOrderStatus({ status: 'PENDING_PAYMENT', ...delivery }, 'CANCELLED')).toBe(true)
+  })
+
   it('PAID → IN_PROGRESS', () => {
     expect(canTransitionAdminOrderStatus({ status: 'PAID', ...delivery }, 'IN_PROGRESS')).toBe(true)
   })