feat: add user management

backend/src/user/dto/createUser.dto.ts

@@ -0,0 +1,14 @@
+import { Expose, plainToClass } from "class-transformer";
+import { Allow } from "class-validator";
+import { UserDTO } from "./user.dto";
+
+export class CreateUserDTO extends UserDTO{
+
+  @Expose()
+  @Allow()
+  isAdmin: boolean;
+
+  from(partial: Partial<CreateUserDTO>) {
+    return plainToClass(CreateUserDTO, partial, { excludeExtraneousValues: true });
+  }
+}