feat: add workspace fs-at seam and retained root lease

backend/package.json

@@ -7,7 +7,9 @@
     "prebuild": "node scripts/clean-dist.mjs",
     "build": "tsc -p tsconfig.json",
     "test": "vitest run",
-    "start": "node dist/server.js"
+    "start": "node dist/server.js",
+    "build:native": "node scripts/build-workspace-fs-at.mjs",
+    "postinstall": "npm run build:native"
   },
   "dependencies": {
     "@fastify/cors": "^11.2.0",
@@ -18,7 +20,8 @@
     "yaml": "^2.9.0",
     "yauzl": "^3.4.0",
     "yazl": "^3.3.1",
-    "zod": "^4.4.3"
+    "zod": "^4.4.3",
+    "fs-ext": "2.1.1"
   },
   "devDependencies": {
     "@types/node": "^22.0.0",
@@ -26,6 +29,10 @@
     "@types/yazl": "^3.3.1",
     "tsx": "^4.19.0",
     "typescript": "^5.6.0",
-    "vitest": "^2.1.0"
+    "vitest": "^2.1.0",
+    "node-gyp": "11.2.0"
+  },
+  "engines": {
+    "node": ">=22 <23"
   }
 }