Create GraphQLClient using user_pool rather than api_key in appsync-lambda-bedrock-async-stream-subscription-cdk

[alindsharmasimply]

Kindly suggest how can the following pattern be used if the application uses COGNITO_USER_POOLS for auth.

In the current codebase the lambda uses APPSYNC_API_KEY in the GraphQLClient headers as follows:
const graphQLClient = new GraphQLClient(process.env.APPSYNC_ENDPOINT!, { headers: { 'x-api-key': process.env.APPSYNC_API_KEY! }, });

I understand using the User_Pool for appsync auth. Beyond that, what can be done?