chore: added Expo example

[gorhom]

Motivation

This pr will introduce a new Expo example alongside the current ( bare react native ), this will allow testing the library on web.

[henrikra]

Maybe you could have added README to the example expo folder?

At least when I first ran inside example/expo folder yarn install and then npm run ios I am getting this error and the app won't start.

So could you also make PR which adds documentation on how to run the expo example app?

Here is the full error log

Error: Invalid hook call. Hooks can only be called inside of the body of a function component. This could happen for one of the following reasons:
1. You might have mismatching versions of React and the renderer (such as React DOM)
2. You might be breaking the Rules of Hooks
3. You might have more than one copy of React in the same app
See https://reactjs.org/link/invalid-hook-call for tips about how to debug and fix this problem.

This error is located at:
    in App (created by _default)
    in _default (created by ExpoRoot)
    in ExpoRoot
    in RCTView (created by View)
    in View (created by AppContainer)
    in DevAppContainer (created by AppContainer)
    in RCTView (created by View)
    in View (created by AppContainer)
    in AppContainer
    in main(RootComponent)
at node_modules/react-native/Libraries/Core/ExceptionsManager.js:95:4 in reportException
at node_modules/react-native/Libraries/Core/ExceptionsManager.js:141:19 in handleException
at node_modules/react-native/Libraries/Core/ReactFiberErrorDialog.js:52:4 in showErrorDialog
at node_modules/react-native/Libraries/ReactNative/renderApplication.js:76:4 in renderApplication
at node_modules/react-native/Libraries/ReactNative/AppRegistry.js:119:8 in runnables.appKey.run
at node_modules/react-native/Libraries/ReactNative/AppRegistry.js:213:4 in runApplication

Error: Invalid hook call. Hooks can only be called inside of the body of a function component. This could happen for one of the following reasons:
1. You might have mismatching versions of React and the renderer (such as React DOM)
2. You might be breaking the Rules of Hooks
3. You might have more than one copy of React in the same app
See https://reactjs.org/link/invalid-hook-call for tips about how to debug and fix this problem.

This error is located at:
    in App (created by _default)
    in _default (created by ExpoRoot)
    in ExpoRoot
    in RCTView (created by View)
    in View (created by AppContainer)
    in DevAppContainer (created by AppContainer)
    in RCTView (created by View)
    in View (created by AppContainer)
    in AppContainer
    in main(RootComponent)
at node_modules/react-native/Libraries/Core/ExceptionsManager.js:95:4 in reportException
at node_modules/react-native/Libraries/Core/ExceptionsManager.js:141:19 in handleException
at node_modules/react-native/Libraries/Core/setUpErrorHandling.js:24:6 in handleError
at node_modules/expo-error-recovery/build/ErrorRecovery.fx.js:12:21 in ErrorUtils.setGlobalHandler$argument_0

[henrikra]

Looks like the same error is present when I try to run the bare version so it is not only related to Expo.

Would it be possible to add documentation on how to run examples?