read abstract method
Reads an existing session or creates a new one if it does not exist.
This method retrieves a session associated with the given request and
session name. If a session exists, it's loaded; otherwise, a new session
is created.
The request object provides context, including cookies or headers used to
identify the session. The name parameter uniquely identifies the session.
Returns a Future<Session> that completes with the loaded or newly created
Session object.
Example:
final session = await store.read(request, 'my_session');
Implementation
FutureOr<Session> read(Request request, String name);