Add robots.txt and sitemap.xml for SEO

Author: alexisrc1

examples/official-site/robots.txt

@@ -0,0 +1,8 @@
+User-agent: *
+Disallow: /examples/authentification/  # Block the folder "authentification" to avoid blocking by password
+Disallow: /examples/hash_password.sql  # Block access to specific sensitive SQL files like this
+Disallow: /Dockerfile  # Block access to Dockerfile
+
+Allow: /  # Allow access to all public-facing SQL-generated pages
+
+Sitemap: https://sql.datapage.app/sitemap.xml

examples/official-site/sitemap.xml

@@ -0,0 +1,23 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9">
+  <url>
+    <loc>https://sql.datapage.app/</loc>
+    <lastmod>2024-10-10</lastmod>
+    <priority>1.00</priority>
+  </url>
+  <url>
+    <loc>https://sql.datapage.app/component.sql</loc>
+    <lastmod>2024-10-10</lastmod>
+    <priority>0.80</priority>
+  </url>
+  <url>
+    <loc>https://sql.datapage.app/documentation.sql</loc>
+    <lastmod>2024-10-10</lastmod>
+    <priority>0.80</priority>
+  </url>
+  <url>
+    <loc>https://sql.datapage.app/your-first-sql-website/</loc>
+    <lastmod>2024-10-10</lastmod>
+    <priority>0.80</priority>
+  </url>
+</urlset>