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DESCRIPTION
A regression was introduced in Plasma 6.7.0 regarding how kwin_wayland handles multi-GPU setups. Under the new multi-GPU explicit sync and swapchain behavior, KWin automatically creates background rendering pipelines and maps processes across all available system GPUs, even secondary, display-less cards used strictly for compute.

When a heavy parallelized compute workload (such as llama.cpp processing a large context window) saturates the execution queues of the secondary GPU, KWin's compositor frame-scheduling logic misses its synchronization deadlines. This causes the compositor to time out, crashing the llama server/process.

STEPS TO REPRODUCE
1. Boot into a Plasma 6.7.0 Wayland session on a multi-GPU setup (e.g., primary RTX 5070 Ti driving displays, secondary RTX 5060 Ti as an internal compute node).
2. Run nvidia-smi to confirm that kwin_wayland is now spawning background graphical processes on the secondary compute GPU.
3. Initiate a heavy multi-GPU CUDA workload via llama.cpp using both cards simultaneously.

OBSERVED RESULT
The compositor hits a synchronization watchdog timeout on the secondary card, causing a rendering freeze, shell panic, and a crash of llama server or process utilizing multi-GPU processing.

EXPECTED RESULT
The compositor should cleanly isolate desktop workspace rendering to the primary card or gracefully handle compute-induced sync delays on secondary cards without triggering watchdog for heavy multi-GPU workloads.

SOFTWARE/OS VERSIONS
Operating System (available in the Info Center app, or by running `kinfo` in a terminal window):
KDE Plasma Version: 6.7.0
KDE Frameworks Version: 6.3.0
Qt Version: 6.7.1

ADDITIONAL INFORMATION
Downgrading back to Plasma 6.6.5 completely fixes the issue. Under 6.6.5, nvidia-smi confirms that kwin_wayland restricts its processes entirely to GPU 0 (the primary display card) and leaves the secondary compute card completely uninhibited, preventing any cross-talk timeouts. Using the KWIN_DRM_DEVICES environment variable to manually bypass this in 6.7.0 unfortunately results in a black screen at boot.