is there any open source library or tool that allows managing RESTful resources using static files and synching the state of the remote resources with the static files ?
I found some open source libraries or tools that may help you with managing RESTful resources using static files and synching the state of the remote resources with the static files. Here are some of them:

Seafile is an open source file sync and share solution that supports syncing files across devices and teams, accessing files in the cloud without downloading them, and encrypting files before syncing them. It also has a built-in Wiki feature for knowledge management.
Syncthing is an open source continuous file synchronization program that synchronizes files between two or more computers. It is decentralized, secure, and cross-platform. It does not require a central server or cloud service to operate.
RestFS is an open source RESTful file system that exposes a file system as a RESTful web service. It allows clients to create, read, update, and delete files and directories using HTTP methods. It also supports file locking, versioning, and caching.
I hope these tools can meet your needs.
Thank you for suggesting these tools, I'll definitely look into them and see if they meet my requirements for managing RESTful resources using static files and keeping them in sync.
You're welcome! I'm glad I could provide some options for you to explore. If you have any further questions or need assistance with anything else, please don't hesitate to ask. Good luck with your project!