Add a scan button to bookmarked accounts

When we bookmark, we also save the account's current classification. This should be an array. If a user is on the bookmark page, rescan the account. When it changes, a new classification is added to the history.

Start at the bookmark page and trace the existing logic that saves an account's current classification. Add the scan-button behavior so bookmarked accounts are rescanned, classifications are stored as an array, and changed classifications are appended to history; done means the bookmark page preserves prior classifications and records new ones.

Written by the indexing model from the issue text.