The catalogue is named or absent, the scanner reads both key orders, the loader has unit tests

Review findings: a sibling-path fallback read a catalogue the receipt never claimed;
a manifest literal naming its version first slipped the fence; the shared loader
thirteen beds install through had no test short of a lab run.

test/integration/harness.ts

@@ -241,7 +241,9 @@ export const FILTER_MODULE = "nftables";
 
 /**
  * The catalogue's `modules/` directory: MESH_LAB_CATALOG under either spelling (the checkout, or
- * its modules directory), else the checkout beside this one, the way the main layout has it.
+ * its modules directory). Named, or absent — never guessed from a sibling path: the receipt claims
+ * the catalogue the run was pointed at (src/repos.ts), and a catalogue read from somewhere the
+ * receipt does not name is the drift this exists to close.
  *
  * Beds used to build the manifests they install inline, as literals copied from the catalogue when
  * each bed was written. The copies did not move when the catalogue did, so a catalogue change was
@@ -251,16 +253,14 @@ export const FILTER_MODULE = "nftables";
  */
 export function catalogueDir(): string {
   const named = process.env["MESH_LAB_CATALOG"];
-  const candidates = named
-    ? [resolve(named, "modules"), resolve(named)]
-    : [resolve(process.cwd(), "..", "mesh-catalog", "modules")];
+  if (!named) throw new Error("MESH_LAB_CATALOG is not set to a checkout of mesh-catalog (or its modules directory)");
+  const candidates = [resolve(named, "modules"), resolve(named)];
   for (const dir of candidates) {
     // Known by the registry's manifest, which genesis reads from the catalogue and always will —
     // not the control plane's, which lives in the control plane's own repository (ADR 0069).
     if (existsSync(resolve(dir, "distribution", "module.json"))) return dir;
   }
-  throw new Error(
-    `no catalogue: MESH_LAB_CATALOG=${named ?? "(unset)"} and nothing at ${candidates.join(", ")}`);
+  throw new Error(`no catalogue: MESH_LAB_CATALOG=${named} and no distribution/module.json under ${candidates.join(" or ")}`);
 }
 
 /** Whether a catalogue is where a bed will look — for a skip guard, which says so instead of failing. */