refactor(infra): directory structure (#4615)

packages/backend/storage/tsconfig.json

@@ -0,0 +1,9 @@
+{
+  "extends": "../../../tsconfig.json",
+  "compilerOptions": {
+    "noEmit": false,
+    "outDir": "lib",
+    "composite": true
+  },
+  "include": ["index.d.ts"]
+}