fix: harden Pi lifecycle recovery

backend/test/config.test.ts

@@ -17,6 +17,7 @@ test("loadConfig accepts container listening and runtime paths", () => {
     thtBin: "/opt/venv/bin/tht",
     piBin: "/usr/local/bin/pi",
     settingsFile: "/data/settings/settings.json",
+    maintenanceFile: "/data/settings/maintenance.json",
     dataRoot: "/data",
   });
 });
@@ -29,6 +30,7 @@ test("loadConfig keeps local development defaults", () => {
     thtBin: "tht",
     piBin: "pi",
     settingsFile: "data/settings.json",
+    maintenanceFile: "data/maintenance.json",
     workspaceRegistry: {
       root: "/data/workspace-registry",
       branch: "main",