Host integration

This grid holds links, not rows — so rowNoun: "link" makes the button read + add link and the right-click menu Delete 1 link. The Highlight box marks words without filtering anything (highlightString); the Search box beside it does both, as usual. The footer under the last row is the host's own element (extraElement), lifted clear of the + add link button by one CSS rule, with room for both reserved by whiteSpaceY: 52. Right-click a cell for a host-drawn menu whose icons are matched by item.id.