Replace all emoji icons with Lucide SVGs, add accent color picker

- Replace all emoji characters across WebUI with inline Lucide SVG icons
  for cross-platform consistency (icon paths in icon-paths.js)
- Add accent color picker popover with 9 preset colors + custom picker,
  persisted to localStorage, updates all CSS custom properties
- Remove subtab separator line for cleaner look
- Color badge icons with accent color for visual pop
- Remove processing badge from target cards
- Fix hardcoded #4CAF50 in FPS labels and active badges to use CSS vars
- Replace CSS content emoji (▶) with pure CSS triangle

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

server/src/wled_controller/templates/modals/pattern-template.html

@@ -2,7 +2,7 @@
 <div id="pattern-template-modal" class="modal" role="dialog" aria-modal="true" aria-labelledby="pattern-template-modal-title">
     <div class="modal-content modal-content-wide">
         <div class="modal-header">
-            <h2 id="pattern-template-modal-title" data-i18n="pattern.add">📄 Add Pattern Template</h2>
+            <h2 id="pattern-template-modal-title"><svg class="icon" viewBox="0 0 24 24"><path d="M6 22a2 2 0 0 1-2-2V4a2 2 0 0 1 2-2h8a2.4 2.4 0 0 1 1.704.706l3.588 3.588A2.4 2.4 0 0 1 20 8v12a2 2 0 0 1-2 2z"/><path d="M14 2v5a1 1 0 0 0 1 1h5"/><path d="M10 9H8"/><path d="M16 13H8"/><path d="M16 17H8"/></svg> <span data-i18n="pattern.add">Add Pattern Template</span></h2>
             <button class="modal-close-btn" onclick="closePatternTemplateModal()" title="Close" data-i18n-aria-label="aria.close">&#x2715;</button>
         </div>
         <div class="modal-body">
@@ -36,7 +36,7 @@
                     <small class="input-hint" style="display:none" data-i18n="pattern.visual_editor.hint">Click + buttons to add rectangles. Drag edges to resize, drag inside to move.</small>
                     <div class="pattern-bg-row">
                         <select id="pattern-bg-source"></select>
-                        <button type="button" class="btn btn-icon btn-secondary pattern-capture-btn" onclick="capturePatternBackground()" title="Capture Background" data-i18n-title="pattern.capture_bg">📷</button>
+                        <button type="button" class="btn btn-icon btn-secondary pattern-capture-btn" onclick="capturePatternBackground()" title="Capture Background" data-i18n-title="pattern.capture_bg"><svg class="icon" viewBox="0 0 24 24"><path d="M13.997 4a2 2 0 0 1 1.76 1.05l.486.9A2 2 0 0 0 18.003 7H20a2 2 0 0 1 2 2v9a2 2 0 0 1-2 2H4a2 2 0 0 1-2-2V9a2 2 0 0 1 2-2h1.997a2 2 0 0 0 1.759-1.048l.489-.904A2 2 0 0 1 10.004 4z"/><circle cx="12" cy="13" r="3"/></svg></button>
                     </div>
                     <div class="pattern-canvas-container">
                         <canvas id="pattern-canvas"></canvas>