Cookie consent doesn't work correctly

Once a given user has given consent the box still appears. We need to revisit this as a whole as the whole cookie permissions are inadequate

No files, tests, or entry points are identified in the issue. Start by reproducing the consent flow for a user who has already given consent, then map the existing cookie-permission handling before defining the broader requirements; done means consent is retained and the box no longer reappears, with the permission behavior addressed consistently.

Written by the indexing model from the issue text.