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/icon-calendar.svg

@@ -0,0 +1,6 @@
+<svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="#6366f1" stroke-width="2" stroke-linecap="round" stroke-linejoin="round">
+  <rect x="3" y="4" width="18" height="18" rx="2" ry="2"/>
+  <line x1="16" y1="2" x2="16" y2="6"/>
+  <line x1="8" y1="2" x2="8" y2="6"/>
+  <line x1="3" y1="10" x2="21" y2="10"/>
+</svg>