Make sure Charon default folder is accessible and readable

[boulder225]

🎯 Problem to be solved

We need to check if Charon can access and read its default folder to store files and data. If the folder is not accessible or readable, the application may not work correctly.

🛠️ Proposed solution

• Verify programmatically that the default folder is created and Charon can read/write to it without any permission issues

[gsora]

Is this during DKG or runtime?