Is there a way to dynamically add routes?

I need to serve a static directory which passed by users after the program starts, I tried `CreateRoutes` but it didn't work.
Is there any way to achieve this requirement?

No file or test is named. Start by reading the CreateRoutes API and the framework's static-directory serving entry points, then verify whether routes can be added after startup. Done means establishing a supported approach or clearly documenting that the requested behavior is unavailable.

Written by the indexing model from the issue text.