Fix: prevent double ./cjs/ prefix in main field + fix imports

- Build script was adding ./cjs/ prefix even when main already had it
- Fixed @testing-library/react dependency for tests
- Changed package-style imports to relative imports in rootJs/index.ts
- Bump version to 0.85.5

packages/dev/package.json

@@ -16,7 +16,7 @@
   "sideEffects": false,
   "type": "module",
   "types": "./index.d.ts",
-  "version": "0.85.4",
+  "version": "0.85.5",
   "main": "./cjs/index.js",
   "module": "./index.js",
   "bin": {