Comprehensive SEO and UI improvements across site

SEO Improvements:
- Add Twitter/OG meta tags to gdpr-compliance.php and terms-of-service.php
- Add author bios with E-E-A-T signals to all blog articles
- Add breadcrumb schema markup to key pages
- Create new service pages: price-monitoring.php, competitive-intelligence.php
- Create location pages: london.php, manchester.php, birmingham.php
- Update sitemap.xml with new pages

UI/CSS Improvements:
- Move testimonials section from inline styles to CSS classes
- Standardize hero gradients to #144784 → #179e83 across all pages
- Unify card border styles to border-left: 4px solid #179e83
- Fix CTA gradient direction consistency on location pages
- Standardize breadcrumb colors to #144784
- Replace all purple accent colors (#667eea, #764ba2) with brand colors
- Add CSS variables for brand consistency in main.css

Code Cleanup:
- Delete 6 emergency CSS fix files (button-emergency-fix.css, etc.)
- Remove related-articles-fix.css references from blog articles
- Consolidate styles into main.css

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

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

includes/breadcrumb-schema.php

@@ -0,0 +1,52 @@
+<?php
+/**
+ * Breadcrumb Schema Component
+ * Generates BreadcrumbList structured data for improved SEO
+ *
+ * Usage: Set $breadcrumbs array before including this file
+ * Example:
+ * $breadcrumbs = [
+ *     ['url' => '/', 'label' => 'Home'],
+ *     ['url' => '/blog', 'label' => 'Blog'],
+ *     ['url' => '', 'label' => 'Current Page Title']
+ * ];
+ */
+
+if (!isset($breadcrumbs) || empty($breadcrumbs)) {
+    return;
+}
+
+$base_url = 'https://ukdataservices.co.uk';
+$items = [];
+
+foreach ($breadcrumbs as $index => $crumb) {
+    $position = $index + 1;
+    $item = [
+        '@type' => 'ListItem',
+        'position' => $position,
+        'name' => $crumb['label']
+    ];
+
+    // Add URL for all items except the last one (current page)
+    if (!empty($crumb['url'])) {
+        $url = $crumb['url'];
+        // Ensure URL is absolute
+        if (strpos($url, 'http') !== 0) {
+            $url = $base_url . $url;
+        }
+        $item['item'] = $url;
+    }
+
+    $items[] = $item;
+}
+
+$schema = [
+    '@context' => 'https://schema.org',
+    '@type' => 'BreadcrumbList',
+    'itemListElement' => $items
+];
+?>
+
+<script type="application/ld+json">
+<?php echo json_encode($schema, JSON_PRETTY_PRINT | JSON_UNESCAPED_SLASHES); ?>
+</script>