Scan history is now a right-side sheet that layers over the current view
(typically Resources Hub) instead of a full-page activeView branch. The
sheet opens via the existing navigation event, fetches only when open,
dismisses on Escape or overlay click, and preserves the nested scan-details
and scan-compare sheets intact via Radix portal stacking.
The fetch effect now resets selection and page state on active-node change
exactly once, avoiding a double-fetch on node switches.
Anso
