Introduce REQ-UI-ITEM-ICON (item icons on belts/ports, colored-square fallback, per-pixel-size raster cache) and REQ-UI-RECIPE-ICON (icon-only recipe options in the Miner/Assembler selection dialog). Document the optional recipes.toml `icon` field and cross-reference from REQ-GW-TILE-SIZE and the visuals.toml config description. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01Y7N59FsLA5e2kuVdqe4Uhc