feat: add a react native expo sample app

[beekhc]

Which problem is this PR solving?

We've had several requests for examples of how to use Honeycomb with React Native apps. This example should fulfill that need, once we made this repo public.

Short description of the changes

This is mostly a default React Native Expo app. The main modified files that need to be reviewed are:

• README.md
• app/(tabs)/demo.tsx
• app/honeycomb.tsx

How to verify that this has the expected result

I have manually run this app in the iOS simulator and verified that the intended telemetry shows up in Honeycomb.

[JamieDanielson]

Looks great! A few suggestions below. Still unsure about the error I'm getting locally but will continue to investigate.

[JamieDanielson]

As discussed offline, we'll circle back to sort out the web error from the newly introduced "exports" field in package.json. As it is here it works and that's what we want 🚀