Accidental glyph must not collide with a ledger line

An accidental beside a notehead on/crossing a ledger line must not visually overlap the ledger line stroke.

A high/low ledger-line note (e.g. A5 or C2) with a sharp/flat visually overlaps ledger-line strokes in the rendered SVG.

Gould (general clarity principle, no explicit numeric rule); Ross, explicit ledger-line-clearance discussion. Pure rendering-geometry concern.

This rule is about where marks land on the page, so it can only be judged after engraving. Collision and spacing faults live here.