async setupOutput() {
    if (this.output === 'fs') {
      await this.setupFSOutput();
    } else if (this.output === 'string' && this.entrypoint === undefined) {
      throw new Error('Parameter entrypoint is required when using output = "string"');
    }
  }
Sets up the output configuration based on the specified output type.

@example
const generator = new Generator();
await generator.setupOutput();

@async

@throws {Error} If 'output' is set to 'string' without providing 'entrypoint'.