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/opacity.svg

@@ -0,0 +1 @@
+<svg id="icon" viewBox="0 0 32 32"><title>opacity</title><rect x="6" y="6" width="4" height="4"/><rect x="10" y="10" width="4" height="4"/><rect x="14" y="6" width="4" height="4"/><rect x="22" y="6" width="4" height="4"/><rect x="6" y="14" width="4" height="4"/><rect x="14" y="14" width="4" height="4"/><rect x="22" y="14" width="4" height="4"/><rect x="6" y="22" width="4" height="4"/><rect x="14" y="22" width="4" height="4"/><rect x="22" y="22" width="4" height="4"/><rect x="18" y="10" width="4" height="4"/><rect x="10" y="18" width="4" height="4"/><rect x="18" y="18" width="4" height="4"/></svg>