feat(a11y,ux): implement comprehensive accessibility and UX optimizations

Phase 1: Accessibility Optimizations
- Add proper label associations and ARIA attributes to form inputs
- Implement aria-required, aria-invalid, aria-describedby for better form accessibility
- Add role='alert' for error messages
- Enhance keyboard navigation with aria-expanded, aria-controls
- Add aria-label for mobile menu button
- Implement aria-current for active navigation items
- Add semantic HTML with aria-labelledby for sections

Phase 2: UX Optimizations
- Create loading skeleton components for better loading states
- Add FormSkeleton, SectionSkeleton, and LoadingSkeleton components
- Prepare for lazy loading implementation

Files modified:
- src/components/ui/input.tsx: Enhanced with ARIA attributes
- src/components/ui/textarea.tsx: Enhanced with ARIA attributes
- src/components/layout/header.tsx: Added navigation ARIA labels
- src/components/sections/hero-section.tsx: Added section labels
- src/components/sections/services-section.tsx: Added section labels
- src/components/ui/loading-skeleton.tsx: New loading state components

Impact:
- WCAG 2.1 AA compliance improvements
- Better screen reader support
- Enhanced keyboard navigation
- Improved user feedback during loading

src/components/effects/gradient-flow.tsx

@@ -0,0 +1,35 @@
+'use client';
+
+import { motion } from 'framer-motion';
+
+interface GradientFlowProps {
+  className?: string;
+  colors?: string[];
+  duration?: number;
+}
+
+export function GradientFlow({
+  className = '',
+  colors = ['#C41E3A', '#D4A574', '#8B4513', '#2F4F4F'],
+  duration = 15
+}: GradientFlowProps) {
+  return (
+    <motion.div
+      className={`absolute inset-0 ${className}`}
+      style={{
+        background: `linear-gradient(-45deg, ${colors.join(', ')})`,
+        backgroundSize: '400% 400%'
+      }}
+      animate={{
+        backgroundPosition: ['0% 50%', '100% 50%', '0% 50%']
+      }}
+      transition={{
+        duration,
+        repeat: Infinity,
+        ease: 'linear'
+      }}
+    />
+  );
+}
+
+export default GradientFlow;