feat(qt-integration): implement comprehensive Qt integration for modern UI

- Added a new Qt-based user interface for id Tech 3, enhancing the overall user experience with modern design elements.
- Introduced various UI components including asset browser, console widget, and main menu, providing a cohesive interface for game management.
- Implemented asset management tools, performance profiling, and mod management features, improving usability and functionality.
- Enhanced CMake configuration to support Qt integration, allowing users to enable or disable features as needed.
- Created detailed documentation outlining the new Qt integration system, including architecture and usage guidelines.

This commit significantly modernizes the user interface and experience for id Tech 3, paving the way for future enhancements and community contributions.

Author: timfox

CMakeLists.txt

@@ -4244,6 +4244,63 @@ ENDIF()
 # Add include directories for q3ui
 TARGET_INCLUDE_DIRECTORIES(q3ui PRIVATE ${CMAKE_CURRENT_SOURCE_DIR}/src ${CMAKE_CURRENT_SOURCE_DIR}/src/client)
 
+# Qt Integration - Modern UI Development
+OPTION(USE_QT "Enable Qt integration for modern UI" OFF)
+IF(USE_QT)
+	FIND_PACKAGE(Qt6 REQUIRED COMPONENTS Core Widgets OpenGL Network Charts)
+	SET(CMAKE_AUTOMOC ON)
+	SET(CMAKE_AUTORCC ON)
+	SET(CMAKE_AUTOUIC ON)
+
+	FILE(GLOB QT_SRCS
+		"src/qt/*.cpp"
+		"src/qt/*.h"
+		"src/qt/*.qrc"
+	)
+
+	# Exclude launcher from main build (it's standalone)
+	LIST(FILTER QT_SRCS EXCLUDE REGEX ".*qt_launcher\\.cpp$")
+
+	IF(QT_SRCS)
+		# Add Qt integration to main engine
+		TARGET_SOURCES(${CMAKE_PROJECT_NAME} PRIVATE ${QT_SRCS})
+
+		TARGET_LINK_LIBRARIES(${CMAKE_PROJECT_NAME}
+			Qt6::Core
+			Qt6::Widgets
+			Qt6::OpenGL
+			Qt6::Network
+			Qt6::Charts
+		)
+
+		TARGET_COMPILE_DEFINITIONS(${CMAKE_PROJECT_NAME} PRIVATE QT_ENABLED)
+		TARGET_INCLUDE_DIRECTORIES(${CMAKE_PROJECT_NAME} PRIVATE src/qt)
+
+		# Create standalone Qt launcher
+		FILE(GLOB LAUNCHER_SRCS "src/qt/qt_launcher.cpp" "src/qt/idtech3_resources.qrc")
+		IF(LAUNCHER_SRCS)
+			ADD_EXECUTABLE(qt_launcher ${LAUNCHER_SRCS})
+
+			TARGET_LINK_LIBRARIES(qt_launcher
+				Qt6::Core
+				Qt6::Widgets
+				Qt6::Network
+			)
+
+			TARGET_COMPILE_DEFINITIONS(qt_launcher PRIVATE QT_STANDALONE)
+			TARGET_INCLUDE_DIRECTORIES(qt_launcher PRIVATE src/qt)
+			MESSAGE(STATUS "Qt launcher: enabled")
+		ENDIF()
+
+		MESSAGE(STATUS "Qt integration: enabled")
+	ELSE()
+		MESSAGE(WARNING "Qt integration requested but no source files found")
+		SET(USE_QT OFF)
+	ENDIF()
+ELSE()
+	MESSAGE(STATUS "Qt integration: disabled")
+ENDIF()
+
 # UI2 - Deterministic UI/Layout System (C++23)
 OPTION(USE_UI2 "Enable UI2 deterministic UI/layout system" OFF)
 IF(USE_UI2)