feat(wood-paneling): create wood paneling management system

- Add woodPaneling.ts with localStorage-based paneling preferences
- Add woodPanelingInit.ts for early initialization (prevents flash)
- Support none, wood-light, wood-dark, wood-mahogany options
- Apply paneling to #collections-container only (not full body)
- Use Tailwind utility classes for backgrounds
- Use CSS variable classes for active indicators
- Export functions for HTML onclick handlers
- Auto-initialize on DOM ready

web/src/woodPanelingInit.ts

@@ -0,0 +1,24 @@
+// Early initialization script to prevent flash of wrong background
+// Loads before woodPaneling.js to apply paneling immediately
+
+const WOOD_INIT_STORAGE_KEY = 'wood-paneling';
+
+// Apply wood paneling immediately (before DOM ready if possible)
+(function() {
+    const woodPaneling = localStorage.getItem(WOOD_INIT_STORAGE_KEY) || 'none';
+    if (woodPaneling !== 'none') {
+        const applyPaneling = () => {
+            const container = document.getElementById('collections-container');
+            if (container) {
+                container.classList.add(`bg-${woodPaneling}`);
+            }
+        };
+
+        // Apply immediately if DOM is ready, otherwise wait
+        if (document.readyState === 'loading') {
+            document.addEventListener('DOMContentLoaded', applyPaneling);
+        } else {
+            applyPaneling();
+        }
+    }
+})();