Security hardening + new tools deployment

- Hide Apache version (ServerTokens Prod)
- Add Permissions-Policy header
- Remove deprecated X-XSS-Protection
- Consolidate security headers to .htaccess only (remove duplicates from PHP)
- Deploy free tools: robots-analyzer, data-converter
- Deploy tools announcement blog post
- Update sitemap with new tools and blog post

sitemap-tools.xml

@@ -0,0 +1,33 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9">
+    <url>
+        <loc>https://ukdataservices.co.uk/tools/</loc>
+        <lastmod>2026-02-04</lastmod>
+        <changefreq>monthly</changefreq>
+        <priority>0.7</priority>
+    </url>
+    <url>
+        <loc>https://ukdataservices.co.uk/tools/cost-calculator</loc>
+        <lastmod>2026-02-04</lastmod>
+        <changefreq>monthly</changefreq>
+        <priority>0.8</priority>
+    </url>
+    <url>
+        <loc>https://ukdataservices.co.uk/tools/scrapeability-checker</loc>
+        <lastmod>2026-02-04</lastmod>
+        <changefreq>monthly</changefreq>
+        <priority>0.8</priority>
+    </url>
+    <url>
+        <loc>https://ukdataservices.co.uk/tools/robots-analyzer</loc>
+        <lastmod>2026-02-04</lastmod>
+        <changefreq>monthly</changefreq>
+        <priority>0.8</priority>
+    </url>
+    <url>
+        <loc>https://ukdataservices.co.uk/tools/data-converter</loc>
+        <lastmod>2026-02-04</lastmod>
+        <changefreq>monthly</changefreq>
+        <priority>0.8</priority>
+    </url>
+</urlset>