[TIMOB-24455] Windows: Allow custom Extensions in manifest root

Following up from TIMOB-24282 In tiapp.xml, we should be able to define Extensions in App's root, not under the Package's root. {quote} " it is mentioned that by modifying tiapp.xml, one can add Extensions and while it was tried, it seems those elements are copied inside the App's root and not the Package's. It needs to be in the latter. With that being said, there is also a mention of using CMake to include files and it seems that this approach regenerates the solution file. That being so, if there is a way to use that approach such that the we can add compile-time references to some of the third-party binaries (that is, not just include them as "resources"), I believe Visual Studio will also add the appropriate elements to register the classes from the SDK in the Package's AppManifest. {quote}