Merge floating particles into WebGL shader and fix color picker clipping

Remove overflow:hidden from .card and .template-card that was clipping
the color picker popover. Combine noise field + particle glow into a
single GPU shader pass (40 drifting particles as uniforms).

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

server/src/wled_controller/static/css/cards.css

@@ -56,7 +56,6 @@ section {
     border-radius: 8px;
     padding: 12px 20px 20px;
     position: relative;
-    overflow: hidden;
     transition: transform 0.2s ease, box-shadow 0.2s ease, border-color 0.2s ease;
     display: flex;
     flex-direction: column;