Add log field to track user/session

[Matt-Spence]

Issue description

Currently it is difficult to correlate logs for a given user/session. This can make debugging specific issues tricky. We should add a field to logs that enables us to filter them by user. This field should be user-specific but appropriate for inclusion in logs (e.g. an email address). This may be either a separate field within the log, or pre-pended onto the log message itself.

Acceptance criteria

• Logs include an element that enables them to be correlated by user

Additional context

No response

Links to other issues

No response