Judge tests that read another repository against what the check clones, never the desktop's checkout (issue 432)

Tests that read ../../../mesh-catalog or ../../../mesh-host gave a verdict
that depended on what sat beside the checkout: a stale or dirty sibling
failed them on a desktop, and a missing one skipped them unseen. They now
read the clone the build seat puts in MESH_CHECK_BESIDE, failing when it is
absent there, and elsewhere a copy captured at a named commit.

The skip had hidden that the builder test read a module retired by ADR 0190.
The systemd reading test no longer counts the machine's own environment.d.

testdata/beside/mesh-catalog/modules/telegram/module.json.captured

@@ -0,0 +1,78 @@
+{
+  "module": "telegram",
+  "version": "1",
+  "slug": "tgrm",
+  "runs-as": "telegram",
+  "claims": [
+    {
+      "name": "channel",
+      "scope": "mesh",
+      "kind": "telegram",
+      "capabilities": [
+        "deliver",
+        "reaches-away",
+        "silent",
+        "edit",
+        "max-length:4096",
+        "choice",
+        "verified-sender",
+        "exact-render",
+        "code-factor"
+      ]
+    },
+    {
+      "name": "intake",
+      "scope": "mesh",
+      "kind": "telegram"
+    }
+  ],
+  "state": [
+    "offset",
+    {
+      "name": "messages",
+      "ttl-seconds": 2592000
+    }
+  ],
+  "own-secrets": {
+    "broker": "${dir:state}/broker",
+    "telegram-token": "${dir:state}/telegram-token"
+  },
+  "secrets-owner": "telegram",
+  "tools": [
+    "telegram_status"
+  ],
+  "resources": [
+    {
+      "id": "account",
+      "type": "user",
+      "name": "telegram",
+      "shell": "/usr/bin/nologin",
+      "home": "/var/lib/telegram"
+    },
+    {
+      "id": "state",
+      "type": "directory",
+      "mode": "0700",
+      "owner": "telegram",
+      "place": "."
+    }
+  ],
+  "build": {
+    "artifacts": [
+      {
+        "name": "tools",
+        "kind": "bundle",
+        "language": "go",
+        "system": "arch",
+        "from": "cmd/telegram",
+        "binary": "telegram",
+        "loads": [
+          "telegram"
+        ],
+        "env": {
+          "MESH_TELEGRAM_TOKEN_FILE": "${dir:state}/telegram-token"
+        }
+      }
+    ]
+  }
+}