Text strikeout

[ickshonpe]

Objective

Add minimal strikeout support for text.

Solution

• Insert the new Strikeout component on any Text, Text2d, or TextSpan entity and its text will be drawn with strikeout.
• The strikeout geometry is stored in TextLayoutInfo in the vec with the section bounding rects.
• Rendering is trivial, identical to drawing text background colours except it's a narrower rect drawn in front instead of behind.
• Text shadows also have strikeout if the text does.

This implementation can easily be expanded to support underline, I've already made a follow up PR that does this here: #21559.

Testing

cargo run --example strikeout

Showcase