monorepo - Setup testing

[gothfemme]

we need to add tests and some commands to run them, some initial thoughts:

• Jest + React Testing Library's probably fine for unit tests in react libraries
• Playwright for E2E would be good too...
• Also should add a command to run them
• Ideally there's some config package broken out similar to how ESlint/TSconfigs are so different packages can use whatever makes sense
• Also need to add a github action to run them