File-based JSON session store.
Stores each session as a JSON file at:
{base_path}/{app_name}/{user_id}/{session_id}.json
Good for development and simple deployments.
Usage
ADK.Session.start_link(
app_name: "my_app",
user_id: "user1",
session_id: "sess1",
store: {ADK.Session.Store.JsonFile, [base_path: "/tmp/sessions"]}
)