Types from imported headers clutter user types

Additional Information:

I'm often using "Analysis > Import Header File" feature to include headers from external libraries used by a binary I'm analysing. This however means that I can no longer easily list all the types I created for the structures internal to the binary, as these are mixed together with all the imported types.

Is your feature request related to a problem?

Types from imported headers clutter other user types.

What is the feature you'd like to have?

Not sure what, but something that would resolve the problem.
Ideas:

• Allow creating libraries and importing header file to libraries instead of user types.
• Allow grouping user types and importing header file into specified group.
• Automatically grouping imported types by filename.
• Allow filtering manually created structures (i.e. not imported ones).

Are any alternative solutions acceptable?

Prefixing names of manually created types with some unique string. In theory could be done manually, but that's pretty cumbersome and error-prone.

Start at the Analysis > Import Header File workflow described in the issue and investigate how imported types and manually created user types are currently presented. Compare the proposed grouping, library, filename, and filtering approaches. Done means users can distinguish or isolate their manually created types without cumbersome name prefixes.