Add item icon art for all 41 item types

Self-contained full-color SVGs in data/icons/items/, one per item id, read
by the recipe-selection dialog (REQ-UI-RECIPE-ICON) and belt/port rendering
(REQ-UI-ITEM-ICON). Bold silhouette + dark outline, authored to stay legible
at ~16px belt size: rocky ore chunks, isometric ingots, riveted plates,
copper coil/wire, pictorial module devices, and dart hull silhouettes tinted
per fleet color. No config changes needed — each recipe's icon resolves to
its first output.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Y7N59FsLA5e2kuVdqe4Uhc

bin/app/data/icons/items/control_chip.svg

@@ -0,0 +1,6 @@
+<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 100 100" width="100" height="100">
+  <rect x="20" y="20" width="60" height="60" rx="11" fill="#1f7a44" stroke="#0e3320" stroke-width="4"/>
+  <rect x="33" y="33" width="34" height="34" rx="5" fill="#3fbf6a" stroke="#0e3320" stroke-width="3"/>
+  <path d="M50 33 L50 24 M50 67 L50 76 M33 50 L24 50 M67 50 L76 50" stroke="#186036" stroke-width="4" stroke-linecap="round"/>
+  <circle cx="50" cy="50" r="6" fill="#c9a227" stroke="#0e3320" stroke-width="2"/>
+</svg>