feat: self-host all JS/CSS (GDPR) + clicksports map tiles

- Leaflet, TopJSON, Chart.js, Mermaid served from /js/
- Leaflet CSS from /css/leaflet.min.css
- World atlas GeoJSON from /data/countries-110m.json
- Zero external CDN requests (GDPR compliant)
- Map tiles from maps.clicksports.de (fixed missing Noto Sans font)
- Attribution: clicksports maps + OpenMapTiles + OpenStreetMap
- window.load for script initialization (load order fix)

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

layouts/shortcodes/law-charts.html

@@ -34,9 +34,9 @@
   </div>
 </div>
 
-<script src="https://cdn.jsdelivr.net/npm/chart.js@4.4.7/dist/chart.umd.min.js"></script>
+<script src="{{ "js/chart.umd.min.js" | relURL }}"></script>
 <script>
-document.addEventListener('DOMContentLoaded', function() {
+window.addEventListener('load', function() {
   var LANG = "{{ $lang }}";
   var countries = {{ $countries | jsonify }};