Where does the bell icon sit in the Crow's Nest header?
Bell sits in the content header bar, right of the page title, left of the theme toggle. Gold badge shows unread count. Visible from every panel.
Click the bell to open a dropdown showing recent notifications. Unread items have a subtle accent background. Each has an icon, title, timestamp, type badge, and dismiss (x) button. Clicking the title navigates to action_url.