kaomojiFaceSvg function
The approved sprite frame for face: the 24-grid root (round caps
and joins, no fills) wrapping the face group with its 1.45× content
scale and 1.4 stroke. The sprite's .t/.b classes resolve to
inline strokes in the brand palette — flutter_svg renders no
<style> blocks.
Implementation
String kaomojiFaceSvg(KaomojiFace face) =>
'<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24" '
'fill="none" stroke-linecap="round" stroke-linejoin="round">'
'<g transform="translate(12 12) scale(1.45) translate(-12 -12)" '
'stroke-width="1.4">${_stroked(face.svg)}</g></svg>';