Added maxSize and maxAge options to the Mapping class. These are needed in follow-up PR (#2903).

Added two builder functions: createCacheMap() and createLazyMap(). This way the user of the class needs to decide if the Mapping if is a cache or just a lazy loading map. For caches it is required to configure maxSize.

Type safety

The constructor of Mapping is annotated as @internal so that in encourages the usage of the builder functions. If we make it private, the builder functions needs to have access to it somehow. Could e.g. be static methods. Or we could export Mapping as a type.

Testing

In unit tests we test the basic functionality for the lazy map, and use cache map only test the size limitations. This is maybe ok as in the Mapping the differences are abstracted out to the delegate (which is either a LRU cache or plain Map).

Future improvements

• Use Mapping instead of CacheMap in StreamRegistry/StreamStorageRegistry and remove the CacheMap class