feat: implement accessibility tools and named colors explorer

Add comprehensive accessibility features and color naming:

**Color Utilities (lib/utils/color.ts):**
- getRelativeLuminance() - WCAG 2.1 luminance calculation
- getContrastRatio() - Contrast ratio between two colors
- hexToRgb() - Convert hex to RGB
- checkWCAGCompliance() - AA/AAA compliance checker
- Full WCAG 2.1 specification implementation

**New UI Component:**
- Badge component - Status indicators
  - Variants: default, success, warning, destructive, outline
  - Used for pass/fail indicators
  - Accessible focus states

**Accessibility Pages:**

1. Contrast Checker (/accessibility/contrast)
   - Dual color pickers (foreground/background)
   - Real-time contrast ratio calculation
   - Live text preview with both colors
   - WCAG 2.1 compliance display:
     - Level AA: Normal text (4.5:1), Large text (3:1), UI (3:1)
     - Level AAA: Normal text (7:1), Large text (4.5:1)
   - Pass/Fail badges for each criterion
   - Swap colors button
   - Visual feedback with color-coded results

2. Accessibility Dashboard (/accessibility)
   - Overview of all accessibility tools
   - Feature cards with icons
   - Educational content about WCAG 2.1
   - Standards explanation (AA vs AAA)
   - Links to each tool

**Named Colors Page (/names):**
- Display all 148 CSS/X11 named colors
- Search by name or hex value
- Sort options (name, hue)
- Responsive grid layout (2-6 columns)
- Click to copy color
- Color name and hex display
- Loading and error states
- Empty state for no results
- Real-time filtering

**Batch Operations Page (/batch):**
- Placeholder "Coming Soon" page
- Feature preview list
- Planned capabilities description
- Professional coming soon message

**Features Implemented:**
- Real WCAG calculations (not approximations)
- Live contrast ratio updates
- Interactive color swapping
- Comprehensive compliance checking
- Educational content
- Named colors from API
- Search and filtering
- Responsive layouts

**Build Status:**
✅ 11 pages successfully rendering
✅ All TypeScript checks passing
✅ No build errors

All major sections now have functional or placeholder pages!

Next: Polish, testing, and additional enhancements.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

app/batch/page.tsx

@@ -0,0 +1,37 @@
+import { FileUp } from 'lucide-react';
+
+export default function BatchPage() {
+  return (
+    <div className="min-h-screen p-8">
+      <div className="max-w-7xl mx-auto space-y-8">
+        <div>
+          <h1 className="text-4xl font-bold mb-2">Batch Operations</h1>
+          <p className="text-muted-foreground">
+            Process multiple colors at once with CSV/JSON upload
+          </p>
+        </div>
+
+        <div className="flex items-center justify-center min-h-[400px]">
+          <div className="text-center space-y-4">
+            <FileUp className="h-16 w-16 mx-auto text-muted-foreground" />
+            <h2 className="text-2xl font-semibold">Coming Soon</h2>
+            <p className="text-muted-foreground max-w-md">
+              Batch operations will allow you to upload CSV or JSON files with multiple colors
+              and apply transformations to all of them at once.
+            </p>
+            <div className="text-sm text-muted-foreground">
+              <p className="font-semibold mb-2">Planned features:</p>
+              <ul className="space-y-1">
+                <li>• Upload CSV/JSON color lists</li>
+                <li>• Bulk format conversion</li>
+                <li>• Apply operations to all colors</li>
+                <li>• Export results in multiple formats</li>
+                <li>• Progress tracking for large batches</li>
+              </ul>
+            </div>
+          </div>
+        </div>
+      </div>
+    </div>
+  );
+}