Icon renders Material Symbols Rounded at weight 300 from a subset font
that holds only the glyphs listed in packages/ui/src/icons/names.ts.
pnpm icons:build checks every name against Google's codepoints and
regenerates the font; a test keeps the manifest and the list in sync.
Icons are aria-hidden and untranslated, and directional ones mirror in
right-to-left layouts.
