Qt6ShaderTools cmake function is not available in our cross-compilation
setup. Added -C preload with no-op stub function to allow cmake
configuration to proceed past shader compilation calls.
Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)
Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>
Consolidate the active desktop path around redbear-full while landing the greeter/session stack and the runtime fixes needed to keep Wayland and KWin bring-up moving forward.
vasilito