Opt-in registration of Razor Class Library

Question

To use a Razor Class Library in a client project, one adds a <ProjectReference>. That references the library's pages and static assets, and automatically registers them - I don't need to perform any other config.

Is it possible to have an "opt in" registration mechanism instead? The same as with other .NET libraries, where referencing them is not enough, one must also register them during startup, e.g.:

services.AddSomeLibrary();

Is there an equivalent way to register a Razor Class Library?