fail2ban's tools are a bundle the node's runtime serves; its container goes (hq to-be 38 WP4)

The second holder follows the packet filter: the container, its base images, the Dockerfile,
and the bus credential and state directory only the container read are gone; the tools are a
TypeScript bundle node-tools loads. The daemon's socket answers only to root, so the client
runs through sudo without a prompt where the runtime's account is not root, naming sudo's
absence or refusal by how it failed; client and daemon are the one package the module declares.

modules/fail2ban/test/client.test.ts

@@ -2,7 +2,7 @@
 // on the control node on 2026-10-02 (novox/hq ADR 0179).
 import { test } from "node:test";
 import assert from "node:assert/strict";
-import { Fail2banClient, parseBans, parseJailStatus, type Runner } from "../client.ts";
+import { Fail2banClient, escalated, installed, parseBans, parseJailStatus, type Runner } from "../client.ts";
 
 const STATUS = "Status\n|- Number of jail:\t2\n`- Jail list:\trecidive, sshd\n";
 const RECIDIVE =
@@ -104,3 +104,11 @@ test("a jail's settings are read from the daemon's listings", async () => {
     logpath: [], journalmatch: "_SYSTEMD_UNIT=sshd.service + _COMM=sshd",
   });
 });
+
+test("the client runs as given by root and through sudo without a prompt by anyone else", () => {
+  assert.deepEqual(escalated("fail2ban-client", ["status"], 0), ["fail2ban-client", ["status"]]);
+  assert.deepEqual(escalated("fail2ban-client", ["set", "sshd", "banip", "198.51.100.7"], 1000),
+    ["sudo", ["-n", "fail2ban-client", "set", "sshd", "banip", "198.51.100.7"]]);
+  assert.equal(installed("sh"), true);
+  assert.equal(installed("no-such-client-of-the-mesh"), false);
+});