ImGui drawing code now takes place in the main thread, a snapshot of the render data is created in CMaterialSystem::SwapBuffers(), and is being rendered in the render thread right before SpinPresent().
The reason why this was necessary, is because ConVar::GetString() isn't thread safe if its not marked FCVAR_MATERIAL_SYSTEM_THREAD or FCVAR_ACCESSIBLE_FROM_THREADS, and we used it for the console suggestions window, which iterates over every ConVar, accessible from threads or not.
The KeyValues class belongs here. Also reimplemented most loading methods for KeyValues, and adjusted the VPK building code to account for it. Pointers to the engine's implementation of KeyValues have been moved to a separate header ('keyvalues_iface.h'), as this allows external tools code to utilize the standalone KeyValues class implementation. Playlist utilities are completely separated from the KeyValues header; these have nothing to do with KeyValues other than manipulating a global KeyValues object for the playlists, and thus have been named as such and moved to rtech/playlists.
* Better structure packing (reduced padding).
* 'CTextLogger::GetFilter' now returns a reference to 'm_itFilter'.
* Added additional setters and getters.
This should fix all bugs and vulnerabilities to the ImGui console. This code has been fuzzed for hours without triggering any exceptions or assertions.
Fix a potential buffer overflow that could be triggered by logging invalid characters to the Dear ImGui console. The incrementation of the loop control variable performed by 'UTF8CharLength' was never validated.
