Solidus OAuth endpoint

[DanielePalombo]

This endpoint should receive the authorizationCode and scope retrieved by embedded component, and using the oauth/token service It should retrieve the id_token and access_token

Using a Specific Bolt OmniAuth Strategy the access_token will be stored in the user session after the SSO login process.

[DanielePalombo]

TBD: Consider to use the Oauth - Omniauth extension or to create a custom Bolt account entity.

[DanielePalombo]

After some consideration, we preferred to avoid making a specific API endpoint in favor of OmniAuth Strategy that is more standard and that can be used on other rails projects.