fix: standardize GraphQL schema UUID field types (#13550)

Closes [#1264](https://github.com/twentyhq/core-team-issues/issues/1264)

packages/twenty-server/src/engine/core-modules/user/dtos/deleted-workspace-member.dto.ts

@@ -19,6 +19,6 @@ export class DeletedWorkspaceMember {
   @Field(() => String, { nullable: true })
   avatarUrl: string | null;
 
-  @Field(() => String, { nullable: true })
+  @Field(() => UUIDScalarType, { nullable: true })
   userWorkspaceId: string | null;
 }

packages/twenty-server/src/engine/core-modules/user/dtos/workspace-member.dto.ts

@@ -56,6 +56,6 @@ export class WorkspaceMember {
   @Field(() => [RoleDTO], { nullable: true })
   roles?: RoleDTO[];
 
-  @Field(() => String, { nullable: true })
+  @Field(() => UUIDScalarType, { nullable: true })
   userWorkspaceId?: string;
 }