Fail2Ban Upgrade: Update monitoring to use `sudo ipset list f2b-HTTP429`

## Parent issue
Part of #12332 — Upgrade fail2ban to 1.1.0-8 with `iptables-ipset-proto6` banaction.

## Task
Update monitoring scripts/dashboards to use the new ipset-based verification command (dummy IPs provided just as examples):

```bash
sudo ipset list f2b-HTTP429
Name: f2b-HTTP429
Type: hash:ip
Revision: 4
Header: family inet hashsize 1024 maxelem 65536 timeout 0
Size in memory: 49544
References: 1
Number of entries: 468
Members:
1.1.1.1 timeout 0
2.2.2.2 timeout 0
```

Previously, fail2ban status was checked via `sudo fail2ban-client status nginx-429`. With the switch to `iptables-ipset-proto6`, the ipset list is the authoritative source for banned IPs.

This may involve updating Grafana dashboards, alerting scripts, or any runbooks that reference the old check command.

This issue requires upgrading https://github.com/internetarchive/openlibrary/pull/12251 t