launcher: configure and preview controller lightbar color
Add an optional lightbar color to launcher settings and pass it to the emulator with --controller-color. Preview changes on RGB gamepads, handle controller hotplug events, and restore the saved color when settings dialogs close. Release launcher preview handles when starting a game.
Co-authored-by: m66401970-eng <m66401970@gmail.com>
uic from Qt 6.12.0 crashes (0xC0000005) on any non-empty <connections>
block in .ui files. Move the cancel_button -> reject connection from
configuration_edit_dialog.ui into configurationEditDialog.cpp, matching
how the other buttons are already connected there.
Also document the glslang (glslangValidator) requirement for Windows
builds; CMake requires it via find_program(... REQUIRED).
Pyxellator