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/mesh-delivery/module.json.captured

@@ -0,0 +1,81 @@
+{
+  "module": "mesh-delivery",
+  "version": "1",
+  "slug": "deliver",
+  "claims": [
+    {
+      "name": "mesh-delivery",
+      "scope": "mesh",
+      "serves": [
+        "deliveries",
+        "times",
+        "show",
+        "groups",
+        "what-if",
+        "checks",
+        "table",
+        "stalled",
+        "recheck",
+        "release",
+        "stop",
+        "close",
+        "retire-history"
+      ]
+    }
+  ],
+  "consumes": [
+    "gitea.pull.updated",
+    "gitea.pull.merged",
+    "gitea.pull.closed",
+    "mesh-controller.checked",
+    "mesh-controller.plan-moved"
+  ],
+  "emits": [
+    "transition",
+    "group"
+  ],
+  "invokes": [
+    "seat:mesh-controller.delivery-plan",
+    "seat:mesh-controller.delivery-order",
+    "seat:mesh-controller.delivery-check",
+    "seat:mesh-controller.deliver",
+    "seat:mesh-controller.delivery-stop",
+    "seat:mesh-controller.delivery-walks",
+    "gitea.gitea_note_append",
+    "gitea.gitea_delivery_view",
+    "gitea.gitea_commit_status",
+    "gitea.gitea_commit_statuses",
+    "gitea.gitea_contains",
+    "gitea.gitea_open_pulls"
+  ],
+  "state": [
+    "deliveries",
+    "groups"
+  ],
+  "tools": [
+    "delivery_status"
+  ],
+  "resources": [
+    {
+      "id": "state",
+      "type": "directory",
+      "mode": "0700",
+      "place": "."
+    }
+  ],
+  "build": {
+    "artifacts": [
+      {
+        "name": "tools",
+        "kind": "bundle",
+        "language": "go",
+        "system": "arch",
+        "from": "cmd/mesh-delivery",
+        "binary": "mesh-delivery",
+        "loads": [
+          "mesh-delivery"
+        ]
+      }
+    ]
+  }
+}