fix: use OSM raster tiles for world map (clicksports vector tiles 503)

maps.clicksports.de vector tile style.json returns 503 on render.
Fall back to OSM raster tiles until tile server is fixed.

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

layouts/shortcodes/world-map.html

@@ -49,7 +49,7 @@
 
   var map = new maplibregl.Map({
     container: 'ifk-world-map',
-    style: 'https://maps.clicksports.de/styles/klokantech-basic/style.json',
+    style: { version: 8, sources: { osm: { type: 'raster', tiles: ['https://tile.openstreetmap.org/{z}/{x}/{y}.png'], tileSize: 256, attribution: '&copy; <a href="https://openstreetmap.org/copyright">OpenStreetMap</a>' } }, layers: [{ id: 'osm', type: 'raster', source: 'osm' }] },
     center: [10, 25],
     zoom: 1.5,
     minZoom: 1,
@@ -84,7 +84,7 @@
             'fill-color': ['get', 'fillColor'],
             'fill-opacity': ['get', 'fillOpacity']
           }
-        }, 'aeroway_fill');
+        });
 
         map.addLayer({
           id: 'choropleth-outline',
@@ -94,7 +94,7 @@
             'line-color': '#94a3b8',
             'line-width': 0.6
           }
-        }, 'aeroway_fill');
+        });
 
         map.addLayer({
           id: 'choropleth-hover',
@@ -105,7 +105,7 @@
             'fill-opacity': 0
           },
           filter: ['==', 'isoNum', '']
-        }, 'aeroway_fill');
+        });
 
         var popup = new maplibregl.Popup({ closeButton: true, closeOnClick: false, maxWidth: '280px' });