v1.9.1: fix world map rendering and resolve eight small TODO items

World map:
- Fix zero-padded ISO numeric ids leaving 31 countries unrendered
  (Brazil, Australia, Belgium, Austria, Algeria and more)
- Fix Russia and Fiji smearing across the full map width at the antimeridian
  by unwrapping ring longitudes and drawing them at both edges
- Crop to 84N-60S, add evenodd fill rule, 174 countries rendered

Improvements:
- Logger::tail() reads backwards in chunks instead of loading the whole file
- External links get rel=noopener noreferrer in footer and Markdown content
- formatDisplayName() cleaned up and guarded against empty input
- Export statistics as CSV (Excel BOM) or JSON
- GeoIP database auto-updates when older than 35 days
- Editor shortcuts Ctrl/Cmd+S to save and Ctrl/Cmd+N for a new page
- Live search filter in the admin content browser
- Content versioning with timestamped .bak copies in content/-backups/

Also removes eight stale TODO entries that were already implemented

cms/templates/assets/footer.mustache

@@ -28,15 +28,15 @@
                             {{#cms_version}}
                             <span class="ms-1 cms-version text-muted">{{cms_version}}</span>
                             {{/cms_version}}
-                            <a href="https://git.noorlander.info/E.Noorlander/CodePress.git" target="_blank" rel="noopener" class="footer-icon cms ms-1" title="{{t_powered_by}} CodePress CMS">
+                            <a href="https://git.noorlander.info/E.Noorlander/CodePress.git" target="_blank" rel="noopener noreferrer" class="footer-icon cms ms-1" title="{{t_powered_by}} CodePress CMS">
                                 <i class="bi bi-cpu"></i>
                             </a>
                             <span class="ms-1">|</span>
-                            <a href="{{author_website}}" target="_blank" rel="noopener" class="footer-icon website" title="{{t_author_website}}">
+                            <a href="{{author_website}}" target="_blank" rel="noopener noreferrer" class="footer-icon website" title="{{t_author_website}}">
                                 <i class="bi bi-globe"></i>
                             </a>
                             <span class="ms-1">|</span>
-                            <a href="{{author_git}}" target="_blank" rel="noopener" class="footer-icon git" title="{{t_author_git}}">
+                            <a href="{{author_git}}" target="_blank" rel="noopener noreferrer" class="footer-icon git" title="{{t_author_git}}">
                                 <i class="bi bi-git"></i>
                             </a>
                         </small>