Consider transparent fallback for response replay

Created by: adamreichold

While #57 provides a functional implementation of "reharvesting" via response replay, it is not clear whether the usability gain of providing a transparent fallback to the network if a response is not stored on disk outweighs the increase in complexity of sourcing some responses from disk and some from the network, c.f. https://github.com/adamreichold/umwelt-info/pull/57#discussion_r945834278