Pen-and-ink art direction with stipple shading

- Cream paper, hand-drawn ink borders, engraving-era type
  (IM Fell English SC, EB Garamond)
- Stipple shadows from a seamless, randomly dotted tile (fixed seed)
- Trust badges are ink stars; Sentry and Elder marked by nameplate
- Smokey's crow art unchanged

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01UQnSw4RRWp8uqpj3nsnnXF

RIVE_CONTRACT.md

@@ -2,7 +2,7 @@
 
 The animator builds `crows.riv` against this file, and the web code drives it from the events in `EVENTS.md`. Both sides build against this file, so change it first and then the code. Each animation exists only because an `EVENTS.md` event fires it.
 
-Style: Duolingo-like. Chunky, expressive crows with big squash-and-stretch reactions and readable silhouettes at 96 pixels. The approve and reject buttons stay in HTML for v1 (see "Why buttons stay in HTML").
+Style: Duolingo-like behavior, pen-and-ink look: cream paper, ink linework, stipple shading (see `ui/src/style.css`). Smokey's crow art (`art/crow.svg`) is the character; keep its silhouette. Chunky, expressive crows with big squash-and-stretch reactions and readable silhouettes at 96 pixels. The approve and reject buttons stay in HTML for v1 (see "Why buttons stay in HTML").
 
 ## Rive approach: data binding, not inputs