Setup oauth for frontend login

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Setup oauth connection to authenticate users to the app. Users will by default land on the login page and requires an access token from the Google oauth process before they can use the app.

Requires:

• Setup google project on GCP
• Get Oauth connection credentials

[lourw]

https://docs.expo.dev/guides/google-authentication/

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Middleware to verify token on all calls to backend: https://stackoverflow.com/questions/33860262/how-to-interact-with-back-end-after-successful-auth-with-oauth-on-front-end

[lourw]

Middleware on frontend to verify that user is logged in