Add OpenIddict validation and refine authentication setup

[rgknp]

Introduced OpenIddict validation configuration, enabling the use of a local OpenIddict server instance and ASP.NET Core host integration. Replaced services.AddAuthentication with services.PostConfigure<AuthenticationOptions> to delegate authentication setup to the SecurityModule and avoid overriding default schemes.

Updated AddAuthenticationLibrary in Startup.cs to conditionally skip JWT Bearer registration when OpenIddict is enabled or a test authentication environment is configured. Removed OpenIddictAuthorizationController registration and added necessary using directives for OpenIddict and options configuration.

These changes improve authentication flexibility and modularity, particularly for development environments running in containers.

Description

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Related issues

Addresses [issue #].

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FHIR Team Checklist

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Semver Change (docs)

Patch|Skip|Feature|Breaking (reason)

[rgknp]

Issue created
#5188