Adjust repo's own includes
Use ForwardingHeaders.
Also only explicitly add the ForwardingHeader dir added to the target include dirs; because KDECMakeSettings from ECM already sets CMAKE_INCLUDE_CURRENT_DIR_IN_INTERFACE, so no need to duplicate that thanks, to Friedrich W. H. Kossebau for pointing that out.
Add AnsiHighlighter and HtmlHighlighter to the ForwardingHeaders
Edited by Ahmad Samir