message: add fat lambda stack to app
diff: from aws_cdk import core
  from the_lambda_trilogy.the_lambda_lith_stack import TheLambdalithStack
  +from the_lambda_trilogy.the_fat_lambda_stack import TheFatLambdaStack
  app = core.App()
  TheLambdalithStack(app, "the-lambda-lith-stack")
  +TheFatLambdaStack(app, "the-fat-lambda-stack")
  app.synth()
  