WordArt rich materials: per-face fills, textures, and edge-profile curves

[apresmoi]

Builds the WordArt composer (/wordart) and the @layoutit/polycss-fonts API into a full material + cross-section system. The composer drives it; the renderer needed no changes (the fonts package returns plain Polygon[]).

@layoutit/polycss-fonts — grouped API + axial engine

composeText's options were regrouped from a ~30-field flat bag into five concerns, and the material engine generalized:

• profile (shape) — one union: "flat" · { edge: "bevel"|"round", raised? } · { curve: CubicBezier }. Round comes in concave / convex; curve is a custom edge defined by a CSS cubic-bezier easing (cssCubicBezier).
• faces (color) — axial material stops down the depth axis t ∈ [0,1]: each polygon takes the nearest stop. Accepts { front?, sides?, back? } (sugar — active faces split the axis evenly; a face set to false is covered by its neighbour, no hole), a single Face, or FaceStop[] for N bands. Face = { color?, texture?, tile? } (texture UV-maps across the whole word; tile repeats vs stretches).
• outline, scale: [x,y], flat drop shadow via depth: 0 + faces.back.offset.
• Browser helpers resolveFace / makeFillTexture turn a high-level fill (solid / gradient / rainbow / texture / image) into a pure Face, keeping composeText browser-free.

/wordart composer

• Per-face materials (Front / Sides / Back), each Solid · Texture (· Gradient · Rainbow · Image on Front, · None on Sides/Back).
• 16 bundled voxel block textures (served locally, same-origin) with a swatch picker per face.
• Profile dropdown (Flat · Bevel · Round in/out · Custom curve) with a draggable cubic-bezier editor + CSS-syntax text field (debounced so dragging stays smooth).
• All controls URL-synced.

Validation

• pnpm test && pnpm build
• 44 polycss-fonts tests (the geometry/API engine — extrude.ts 98.9%, composeText.ts 95.6% line coverage): profile union, axial stops + even split, no-side/covered, custom cubic-bezier, per-face textures + tiling, outline, flat shadow, resolveFace mapping.
• Playwright across /wordart: every fill mode, per-face textures, no-side, custom curve, and shadow render with no console errors. (The canvas fill painter and the React component are covered by these manual runs, not unit tests.)