Deprecate `EndpointExposure.CLOUD_FOUNDRY` and introduce an alternative
implementation based on a pluggable abstraction.
The new `EndpointExposureOutcomeContributor` interface may now be used
to influence `@OnAvailableEndpointCondition` exposure results. Several
infrastructure beans that previously used the condition have been
refactored to always be registered, but tolerate missing endpoints.
A new smoke test application has been added that demonstrates how the
abstraction can be used by a third-party.
Closes gh-41135
Co-authored-by: Phillip Webb <phil.webb@broadcom.com>
73f71d5560