RepositoryMethodContext are now made available for dependency injection via RepositoryConfigurationExtensionSupport.registerBeansForRoot(…). Moved RMC into repository.core package (previously repository.core.support) and only expose factory methods on DefaultRepositoryMethodContext. DRMC also exposes a injection proxy lookup method that creates a proxy equipped with a TargetSource delegating to DRMC.getInstance() (previously ….getContext()). An additional, static DRMC.forMethod(…) allows the creation of a default instance for testing purposes.

Rename getRepository() to getMetadata() on RMC.

Fixes GH-3175.

Avoid nullability in RepositoryMethodContextHolder.getContext(). Introduce shortcut in RepositoryMethodContext to obtain the current thread-local context. Update documentation.