fix(vnc): reduce desktop resource pressure #92

Job	Run time
verify / Lint — no bare sleep in tests/e2e	5s
verify / Cross Compile (linux/amd64, linux/arm64)	41s
verify / Web Build	12s
verify / Performance Benchmark (synthetic 10k, local baseline)	1m 2s
verify / Image Size Regression (BASE-04 ≤ 2GB)	1m 29s
verify / Go Tests	1m 16s
verify / Build (macOS)	41s
create-release	11s
build-binaries (darwin, amd64)	30s
build-binaries (linux, arm64)	33s
build-binaries (darwin, arm64)	30s
build-binaries (linux, amd64)	38s
publish-images / build (admin, deploy/docker/admin/Dockerfile, .)	1m 47s
publish-images / build (managed-user, deploy/docker/managed-user/Dockerfile, .)	2m 27s
publish-images / build (control-plane, deploy/docker/control-plane/Dockerfile, .)	9m 25s
update-homebrew	11s
	21m 38s

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