Graph editor: unified card colors, keyboard focus, color picker button

- Unified graph node colors with card color system (shared localStorage)
- Added color picker palette button to node overlay toolbar
- Auto-focus graph container for keyboard shortcuts to work immediately
- Trap Tab key to prevent focus escaping to footer
- Added mandatory bundle rebuild note to CLAUDE.md files

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

server/src/wled_controller/static/js/features/graph-editor.js

@@ -261,6 +261,8 @@ export async function loadGraphEditor() {
     } finally {
         _loading = false;
     }
+    // Ensure keyboard focus whenever the graph is (re-)loaded
+    container.focus();
 }
 
 export function toggleGraphLegend() {
@@ -816,6 +818,11 @@ function _renderGraph(container) {
 
     container.addEventListener('keydown', _onKeydown);
     container.setAttribute('tabindex', '0');
+    container.style.outline = 'none';
+    // Focus the container so keyboard shortcuts work immediately
+    container.focus();
+    // Re-focus when clicking inside the graph
+    svgEl.addEventListener('pointerdown', () => container.focus());
     _initialized = true;
 }
 
@@ -1457,6 +1464,9 @@ function _onNotificationTest(node) {
 /* ── Keyboard ── */
 
 function _onKeydown(e) {
+    // Trap Tab inside the graph to prevent focus escaping to footer
+    if (e.key === 'Tab') { e.preventDefault(); return; }
+
     // Skip when typing in search input (except Escape/F11)
     const inInput = e.target.matches('input, textarea, select');