Use Microsoft Identity

[BrennanConroy]

Adds Microsoft Identity. Closes https://github.com/dotnet-architecture/eShop/issues/72

• Removed Identity.API project, which hosted the in-memory identity server service.
• Using cookie with oidc and getting an access_token from Microsoft Identity
  • Cookie is how we keep the user logged in in the browser while navigating
  • Using UseTokenLifetime to tie the cookie lifetime to the underlying Microsoft Identity token lifetime
  • access_token is used by HttpClient instances when sending requests to other services (e.g. basket)
• Services use Jwt auth connected to Microsoft Identity so we can authenticate requests from WebApp via HttpClient
  • Added RequireScope(...) to services so we can limit them to specific connections (although today we have a single access token with all the scopes, not sure if there is an easy way to generate multiple? But this is future proofing for if someone adds a new app/client that does want specific scope(s))

Right now each app needs to add some duplicate configuration. We can probably add an aspire component for all this so we can flow the config from apphost.

[davidfowl]

Clean. Needs instructions on how to setup Entra to make this work

[BrennanConroy]

Needs instructions on how to setup Entra to make this work

Opened #3