ultix perf/ops workbench: complete 2026-08-31 optimization pass for VM 5111

Everything for the ultix-streaming (VM 5111, pfv-tsys5) performance pass:
full report + host audit results, staged/gated configs, guest prep + host
one-shot + post-reboot-fix + netcheck lifecycle scripts, grow-root manual
runbook, rolling tracking HUD, questions v1, and the gateway boot-race
hardening units. Applied and verified live 2026-08-31; open work is
tracked in Redmine project 55 as #601-#607. [#602]

💘 Generated with Crush

Assisted-by: Crush:glm-5.2

staged/systemd/ukrrs-rt.slice

@@ -0,0 +1,12 @@
+[Unit]
+Description=UKRRS realtime pool: SDR DSP, video encode, latency-hard work
+Documentation=file:///home/reachableceo/optimize/REPORT.md
+
+[Slice]
+# Exclusive-ish by exclusion: account+batch slices are pinned OFF these cores,
+# so anything placed here keeps headroom even under full compile storm.
+# Interim 8 vCPU: 6-7. Post-upgrade 20 vCPU: 18-19 (edit after resize).
+CPUWeight=10000
+AllowedCPUs=6-7
+MemoryHigh=2147483648
+MemoryMax=4294967296