/dev/icons — recurring design-review workbench

Originally a one-off Phase 4 review surface for the dual-surface icon pair on the TOC redesign. Founder picked Pair B 'Frameless glyphs' on 2026-05-17; rather than delete the route, the pattern was kept: a single /dev/* page per project that renders every candidate for a visual-primitive decision side-by-side at multiple sizes, on multiple backgrounds, inside the real composed context (chip-next-to-icon, drift case, missing-file dimmed case). Alternates live one directory deeper at `apps/deck-shell/src/components/icons/alternates/` and remain importable so the design history stays legible. Future icon families, chip variants, badge styles, button states extend this route with additional sections rather than spawning a new /dev/* route per decision.