feat(slots): add error handling for slot deletion when orders are present

packages/graphql/api/slots.ts

@@ -7,6 +7,7 @@ import { getMinutes } from '@repo/utils/datetime-format';
 import dayjs from 'dayjs';
 
 const ERRORS = {
+  HAS_ORDERS: 'Slot has orders',
   MISSING_DATE: 'Missing date',
   MISSING_SERVICE: 'Missing service',
   MISSING_SERVICE_ID: 'Missing service id',
@@ -39,6 +40,12 @@ export class SlotsService extends BaseService {
   async deleteSlot(variables: VariablesOf<typeof GQL.DeleteSlotDocument>) {
     await this.checkPermission(variables);
 
+    const { slot } = await this.getSlot({ documentId: variables.documentId });
+
+    if (slot?.orders?.length) {
+      throw new Error(ERRORS.HAS_ORDERS);
+    }
+
     const { mutate } = await getClientWithToken();
 
     const mutationResult = await mutate({