Set up data validation on routes

[ross3102]

Set up a solution for handling data validation on our API routes so we don't have to manually verify types, etc.

• Check out https://zod.dev/?id=introduction
• See if any of https://zod.dev/?id=api-libraries might be good for our project
  • probably not, note that many of these aren't very actively maintained
• Set up API types/validation for the sample routes (/example)
  • Also add a PATCH(or PUT idr if it matters) route to partially update a record