Add polycss-fonts package and WordArt composer

[apresmoi]

Summary

• add @layoutit/polycss-fonts: a dependency-free TrueType (glyf) reader, textPolygons/composeText extruders (flat/round/bevel profiles), and a Fontsource-backed Google Fonts loader — framework-agnostic, returns plain Polygon[]
• add composeText WordArt composer: multiline, alignment, line height, glyph scale, underline/strike bars, envelope warps (arch/arc/wave/bulge/cone/slant), hole-safe simplify, optional coplanar merge, and a layered two-color (backColor + oblique) look
• add the /wordart website composer: gallery-identical lil-gui sidebars, searchable font picker, preset tiles, URL-synced state, imperative-rotation stage, and Open-in-CodePen export

Validation

• pnpm test && pnpm build
• Playwright smoke test at /wordart confirms both lil-gui panels mount, presets render, ~1k polygons paint, and the console is error-free