incr: make flags readonly once set

- remove redundant validation

models/baseModels/Item/Item.ts

@@ -76,29 +76,6 @@ export class Item extends Doc {
         throw new ValidationError(this.fyo.t`Rate can't be negative.`);
       }
     },
-    hasBatchNumber: async (value: DocValue) => {
-      const { hasBatchNumber } = await this.fyo.db.get(
-        'Item',
-        this.name!,
-        'hasBatchNumber'
-      );
-
-      if (hasBatchNumber && value !== hasBatchNumber) {
-        const itemEntriesInSLE = await this.fyo.db.count(
-          ModelNameEnum.StockLedgerEntry,
-          {
-            filters: { item: this.name! },
-          }
-        );
-
-        if (itemEntriesInSLE > 0) {
-          throw new ValidationError(
-            this.fyo.t`Cannot change value of Has Batch Number as Item ${this
-              .name!} already has transactions against it. `
-          );
-        }
-      }
-    },
   };
 
   static getActions(fyo: Fyo): Action[] {

models/inventory/InventorySettings.ts

@@ -1,5 +1,5 @@
 import { Doc } from 'fyo/model/doc';
-import { FiltersMap } from 'fyo/model/types';
+import { FiltersMap, ReadOnlyMap } from 'fyo/model/types';
 import { AccountTypeEnum } from 'models/baseModels/Account/types';
 import { ValuationMethod } from './types';
 
@@ -10,6 +10,8 @@ export class InventorySettings extends Doc {
   stockReceivedButNotBilled?: string;
   costOfGoodsSold?: string;
   enableBarcodes?: boolean;
+  enableBatches?: boolean;
+  enableUomConversions?: boolean;
 
   static filters: FiltersMap = {
     stockInHand: () => ({
@@ -25,4 +27,16 @@ export class InventorySettings extends Doc {
       accountType: AccountTypeEnum['Cost of Goods Sold'],
     }),
   };
+
+  readOnly: ReadOnlyMap = {
+    enableBarcodes: () => {
+      return !!this.enableBarcodes;
+    },
+    enableBatches: () => {
+      return !!this.enableBatches;
+    },
+    enableUomConversions: () => {
+      return !!this.enableUomConversions;
+    },
+  };
 }