feat: Add possibility to link files to the current system prompt

- Add linking files to chat
- Rework tokens counting

context/CMakeLists.txt

@@ -3,6 +3,7 @@ add_library(Context STATIC
     ChangesManager.h ChangesManager.cpp
     ContextManager.hpp ContextManager.cpp
     ContentFile.hpp
+    TokenUtils.hpp TokenUtils.cpp
 )
 
 target_link_libraries(Context