Add public interface for ClientCredentialsCacheDurationStore

[mortenlokensr]

• Adds a public interface for ClientCredentialsCacheDurationStore
• Uses interface in DI registration and injection into ClientCredentialsTokenManager
• Can be used to reference and modification in customer client credentials token manager

[Copilot]

Pull request overview

This PR adds a public interface IClientCredentialsCacheDurationStore to enable custom implementations of the client credentials cache duration store. The existing internal ClientCredentialsCacheDurationStore now implements this interface, and dependency injection has been updated to use the interface rather than the concrete type.

Reviewed changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
IClientCredentialsCacheDurationStore.cs	New public interface defining cache duration store contract
ClientCredentialsCacheDurationStore.cs	Updated to implement the new public interface
ClientCredentialsTokenManager.cs	Updated to depend on interface instead of concrete type
ServiceCollectionExtensions.cs	Updated DI registration to register interface mapping
PublicApiVerificationTests.*.verified.txt	Updated test baselines to include new public interface

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[damianh]

Is there an issue or discussion somewhere related to this PR?

[mortenlokensr]

Is there an issue or discussion somewhere related to this PR?

I started a discussion myself:
https://github.com/orgs/DuendeSoftware/discussions/433