Add LGProtocol as a pinned submodule and consume its KVMFR protocol
definitions throughout the client, host, IDD, OBS, and profiler.
Keep Looking Glass framebuffer helpers local while removing duplicated
protocol headers and migrating users to KVMFR-scoped types.
Group the IDD sources and Visual Studio filters by subsystem.
Split the device and swap-chain implementations into focused units,
rename the context classes, and reduce header coupling.
