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/parent-child.svg

@@ -0,0 +1 @@
+<svg id="icon" viewBox="0 0 32 32"><title>parent-child</title><path d="M28,12a2,2,0,0,0,2-2V4a2,2,0,0,0-2-2H4A2,2,0,0,0,2,4v6a2,2,0,0,0,2,2H15v4H9a2,2,0,0,0-2,2v4H4a2,2,0,0,0-2,2v4a2,2,0,0,0,2,2h8a2,2,0,0,0,2-2V24a2,2,0,0,0-2-2H9V18H23v4H20a2,2,0,0,0-2,2v4a2,2,0,0,0,2,2h8a2,2,0,0,0,2-2V24a2,2,0,0,0-2-2H25V18a2,2,0,0,0-2-2H17V12ZM12,28H4V24h8Zm16,0H20V24h8ZM4,4H28v6H4Z"/></svg>