fix: detach relation records in cache on record deletion (#3707)

* fix: detach relation records in cache on record deletion

* fix: fix useGetRelationMetadata tests

packages/twenty-front/src/modules/object-metadata/hooks/useGetRelationMetadata.ts

@@ -0,0 +1,67 @@
+import { useRecoilCallback } from 'recoil';
+
+import { objectMetadataItemFamilySelector } from '@/object-metadata/states/objectMetadataItemFamilySelector';
+import { RelationType } from '@/settings/data-model/types/RelationType';
+import {
+  FieldMetadataType,
+  RelationMetadataType,
+} from '~/generated-metadata/graphql';
+
+import { FieldMetadataItem } from '../types/FieldMetadataItem';
+
+export const useGetRelationMetadata = () =>
+  useRecoilCallback(
+    ({ snapshot }) =>
+      ({ fieldMetadataItem }: { fieldMetadataItem: FieldMetadataItem }) => {
+        if (fieldMetadataItem.type !== FieldMetadataType.Relation) return null;
+
+        const relationMetadata =
+          fieldMetadataItem.fromRelationMetadata ||
+          fieldMetadataItem.toRelationMetadata;
+
+        if (!relationMetadata) return null;
+
+        const relationFieldMetadataId =
+          'toFieldMetadataId' in relationMetadata
+            ? relationMetadata.toFieldMetadataId
+            : relationMetadata.fromFieldMetadataId;
+
+        if (!relationFieldMetadataId) return null;
+
+        const relationType =
+          relationMetadata.relationType === RelationMetadataType.OneToMany &&
+          fieldMetadataItem.toRelationMetadata
+            ? 'MANY_TO_ONE'
+            : (relationMetadata.relationType as RelationType);
+
+        const relationObjectMetadataNameSingular =
+          'toObjectMetadata' in relationMetadata
+            ? relationMetadata.toObjectMetadata.nameSingular
+            : relationMetadata.fromObjectMetadata.nameSingular;
+
+        const relationObjectMetadataItem = snapshot
+          .getLoadable(
+            objectMetadataItemFamilySelector({
+              objectName: relationObjectMetadataNameSingular,
+              objectNameType: 'singular',
+            }),
+          )
+          .valueOrThrow();
+
+        if (!relationObjectMetadataItem) return null;
+
+        const relationFieldMetadataItem =
+          relationObjectMetadataItem.fields.find(
+            (field) => field.id === relationFieldMetadataId,
+          );
+
+        if (!relationFieldMetadataItem) return null;
+
+        return {
+          relationFieldMetadataItem,
+          relationObjectMetadataItem,
+          relationType,
+        };
+      },
+    [],
+  );