i18n considerations

There should be some mechanism to ensure that the UI which is rendered for the user respects their language and specific locale settings.

This should extend to handle (at least, there's probably other things I've forgotten):

- All strings returned for display (including pluralization)
- Right-to-left languages (e.g., Hebrew and Arabic)
- Date and number formatting
- Ensuring layouts scale properly (e.g., for languages such as German which tend to have much longer words)
- Icons and images may have to be modified to convey the intended meaning based on region and/or locale
- Colors may need to be changed based on region/location
- Validations (phone number, address/zip code) may have to be different based on region/location

See https://share.google/aimode/Ki79Osf7BI3JcXl1q