Add rotating gradient border on running LED target cards

Animated conic gradient spins around the card edge using CSS Houdini
@property for smooth angle interpolation. Skips the left edge when
a custom card color stripe is assigned (data-has-color attribute).

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

server/src/wled_controller/static/js/core/card-colors.js

@@ -102,7 +102,7 @@ export function wrapCard({
     const actionsClass = type === 'template-card' ? 'template-card-actions' : 'card-actions';
     const colorStyle = cardColorStyle(id);
     return `
-        <div class="${type}${classes ? ' ' + classes : ''}" ${dataAttr}="${id}"${colorStyle ? ` style="${colorStyle}"` : ''}>
+        <div class="${type}${classes ? ' ' + classes : ''}" ${dataAttr}="${id}"${colorStyle ? ` style="${colorStyle}" data-has-color="1"` : ''}>
             <div class="card-top-actions">
                 ${topButtons}
                 <button class="card-remove-btn" onclick="${removeOnclick}" title="${removeTitle}">&#x2715;</button>

server/src/wled_controller/static/js/features/targets.js

@@ -978,6 +978,7 @@ export function createTargetCard(target, deviceMap, colorStripSourceMap, valueSo
     return wrapCard({
         dataAttr: 'data-target-id',
         id: target.id,
+        classes: isProcessing ? 'card-running' : '',
         removeOnclick: `deleteTarget('${target.id}')`,
         removeTitle: t('common.delete'),
         content: `