The one-node bed supervises the host as a service, so reboot is a real check

Installs the shipped nox-mesh-host launcher and unit in the machine and lets the
installer's --host-service start and enable it, instead of --host-in-background
which cannot survive a reboot. E2 now proves the mesh comes back on its own.

Claude-Session: https://claude.ai/code/session_01D6qtiYU3P9jk3pnAXyAFyx

test/integration/one-node-mesh.test.ts

@@ -492,6 +492,9 @@ before(async () => {
         // The same site N1 re-places the anchor at, so N1 is a no-op and the control plane is not
         // recreated mid-test (its --add-host would otherwise change).
         site: "hosting",
+        // Supervise the host as a service so it survives the reboot check (E2).
+        hostService: true,
+        hostBinary: binary,
         log: (m) => console.log(m),
       });
     } catch (err) {