wiki: add Carbon Design System icons (2673) + pictograms (1000)

- 2673 SVG icons from @carbon/icons v11.82.0 (~2.5 MB)
- 1000 SVG pictograms from Carbon Design System (~2.0 MB)
- Updated 00-overview.md with asset structure and category listing

All icons: 32x32, fill: currentColor, optimized SVG
All pictograms: 24x24, fill: currentColor, SVG

assets/icons/carbon/legend.svg

@@ -0,0 +1 @@
+<svg id="icon" width="32" height="32" viewBox="0 0 32 32"><title>legend</title><rect x="16" y="22" width="14" height="2"/><rect x="4" y="20" width="6" height="6" rx="1"/><rect x="16" y="8" width="14" height="2"/><path d="M9.5,12h-5a.5.5,0,0,1-.4473-.7236l2.5-5.0224a.5206.5206,0,0,1,.8945,0l2.5,5.0225A.5.5,0,0,1,9.5,12Z"/></svg>