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/null-sign.svg

@@ -0,0 +1 @@
+<svg id="icon" width="32" height="32" viewBox="0 0 32 32"> <path d="M30,3.4142l-1.4142-1.4142-3.4317,3.4317c-2.4572-2.1313-5.6536-3.4317-9.1541-3.4317-7.7197,0-14,6.2803-14,14,0,3.5005,1.3004,6.6969,3.4317,9.1541l-3.4317,3.4317,1.4142,1.4142,3.4317-3.4317c2.4572,2.1313,5.6536,3.4317,9.1541,3.4317,7.7197,0,14-6.2803,14-14,0-3.5005-1.3004-6.6969-3.4317-9.1541,0,0,3.4317-3.4317,3.4317-3.4317ZM4,16c0-6.6167,5.3833-12,12-12,2.9492,0,5.649,1.0739,7.7406,2.8452L6.8452,23.7406c-1.7713-2.0916-2.8452-4.7914-2.8452-7.7406ZM28,16c0,6.6172-5.3828,12-12,12-2.9491,0-5.6489-1.074-7.7405-2.8453L25.1547,8.2595c1.7713,2.0916,2.8453,4.7914,2.8453,7.7405Z"/> </svg>