chore: retire pfv-tsys8 and fix stale host-skip comment in deploy-check.sh

pfv-tsys8 is permanently retired. Strike its only doc reference and
correct the stale comment in perf/deploy-check.sh that wrongly listed
pfv-tsys9 as "off the air" (tsys9 is online and in the host array;
tsys8 is the retired host).

💘 Generated with Crush

Assisted-by: Crush:glm-5.2

proxmox/docs/AUDIT-2026-07-29.md

@@ -8,7 +8,7 @@
 dumps + ~05:40 CDT capacity probe). Storage configs read directly from
 `/etc/pve/storage.cfg`, `/etc/exports`, `/etc/fstab` on every host.
 **Hosts online:** tsys1, tsys3, tsys4, tsys5, tsys6, tsys7, tsys9
-**Hosts offline:** tsys2 (Win10, pending rebuild), tsys8 (offline)
+**Hosts offline:** tsys2 (Win10, pending rebuild), tsys8 (retired / permanently offline)
 
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