Set up Fastify project

[crutchcorn]

We should scaffold a Fastify project so we can base our project off of it:

• Remove the existing Kotlin api project
• Move the worker package to the root of the repo
  • This will contain two entrypoints: one for the API backend, and one for worker tasks
  • Use tsc --noEmit for "build"-step
  • Node.js Built-in TypeScript
  • Remove TS-only features
• Set up a Fastify server as the main entrypoint
• Merge with the Faktory migration (Faktory nodejs setup & worker integration #4) and set up the task runner as an alternate entrypoint
• Set up Vitest (initial work in test: add initial unit tests #1) for unit testing
• Set up Drizzle ORM for Postgres