create TDD tests

[Expo: Testing with Jest](https://docs.expo.dev/guides/testing-with-jest/)
[RN: Testing](https://reactnative.dev/docs/testing-overview)
[Detox](https://wix.github.io/Detox/)

## *Tooling*

- [ ] install Jest
- [ ] install React Native Testing Library
- [ ] install Detox

## *Write Tests*

- [ ] unit
- [ ] integration
- [ ] E2E