fix #22883: layout improvements for dot & accidental distance settings & small sizes

A number of related issues mostly having to do with layout of "small" chords with respect to dot and accidental distance.  chord-layout-14 and accidental-9 are the new vtests that exaggerate the effect to make it more obvious.  The other changed vtests show (smaller) effects of these fixes, or in a couple of cases, just needed updating in general.