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/headphones.svg

@@ -0,0 +1 @@
+<svg id="icon" viewBox="0 0 32 32"><title>headphones</title><path d="M25,16V15A9,9,0,0,0,7,15v1A5,5,0,0,0,7,26H9V15a7,7,0,0,1,14,0V26h2a5,5,0,0,0,0-10ZM4,21a3,3,0,0,1,3-3v6A3,3,0,0,1,4,21Zm21,3V18a3,3,0,0,1,0,6Z" transform="translate(0)"/></svg>