How to structure a project in TypeScript

A typical Temporal project written in TypeScript consists of the following components:

project-root/
  activities/
      activity.ts
  workflows/
      workerflow.ts
  workers/
      worker.ts
  starter-script.ts

Activities cannot be in the same file as Workflows and must be separately registered. Activities may be retried, so you may need to use idempotency keys for critical side effects.