The date-range fields and their band on the capture-time axis, the
timeline's bars, labels, scrub/pinch/pan/zoom callbacks and its
sweep/current-bucket/anchored state, and the filter bar's people chips,
mode, eyes-open toggle and gesture reference move from AppWindow onto the
`Library` global. Rust reaches them through window.global::<Library>()
rather than window.set_/get_/on_ on the root, as the earlier commits on
this branch did for the grid's cells, selection, ratings and keywords.
dtourolle
6bf67cefc4