Expose more information from CMake projects to IDEs via CMake File API

Currently the File API support in CMake (and it's predecessor - the CMake server mode) do not expose all relevant / important information about CMake projects.

Here are some things missing, which would be useful to have:

• Expose AutoGen build dir property in File API (need to find location of .ui files for the IDE Code Model)​
• Expose interface libraries and their associated sources to an IDE (File API, server mode, some way, doesn't matter)​ Available in File API since cmake 3.19
• Expose dependency information from add_custom_command calls​
• Expose all Makefile targets (make Foo, make package, make clean, etc.) most are exposed, but not all​