Remove nx dependency, use lerna instead

lerna.json

@@ -1,6 +1,7 @@
 {
   "version": "2.7.25-alpha.3",
   "npmClient": "yarn",
+  "useNx": true,
   "packages": [
     "packages/backend-core",
     "packages/bbui",
@@ -31,4 +32,4 @@
       "loadEnvFiles": false
     }
   }
-}
+}

package.json

@@ -15,10 +15,9 @@
     "husky": "^8.0.3",
     "js-yaml": "^4.1.0",
     "kill-port": "^1.6.1",
-    "lerna": "7.0.0-alpha.0",
+    "lerna": "7.0.2",
     "madge": "^6.0.0",
     "minimist": "^1.2.8",
-    "nx": "^16.2.1",
     "prettier": "^2.3.1",
     "prettier-plugin-svelte": "^2.3.0",
     "rimraf": "^3.0.2",