Is it worth holding the write lock less long?

[LeoniePhiline]

Investigate how axum-sessions' SessionHandle interacts with async-session, and how concurrent requests using the same session interact with the underlying session store.

Is the session data exclusive to a request? Is it shared between concurrent requests? How can we get the latest data? When is the underlying store written and read?

Minimally, after the inner service has responded, the token should be re-read from the session if session data is shared between requests. Returning the latest possible token is especially relevant in PerRequest token regeneration mode.