Find a way to prevent overflowing characters

[JohnnyWestlake]

An example being the character preview window here, with the character escaping bounds. On a technical level this is because the character intentionally draws outside the bounds it specifies for its glyph for stylistic purposes, but by getting the actual geometry and comparing it to the stated bounds it should be possible to make it fit correctly. Something similar to this is already taking place for PNG export to make sure the characters fit properly there

(This also affects the character grid but there's not a sane performant way to fix that whilst still rendering that grid in XAML)