Tech: Self-Hosting Leaflet + Image-Sitemap

- Leaflet 1.9.4 + Markercluster 1.5.3 von unpkg.com lokal nach assets/vendor/leaflet/
  Spart externen DNS-Lookup, gibt Cache-Kontrolle, kein Third-Party-Call
  Inkl. marker/layers Bilder fuer Default-Marker
- preconnect zu unpkg.com aus 8 Seiten entfernt (nicht mehr noetig)
- sitemap.xml: image-Sitemap erweitert
  Pro URL og-image + Logo, Hauptseite zusaetzlich handshake
  Namespace xmlns:image hinzugefuegt

assets/vendor/leaflet/MarkerCluster.css

@@ -0,0 +1,14 @@
+.leaflet-cluster-anim .leaflet-marker-icon, .leaflet-cluster-anim .leaflet-marker-shadow {
+	-webkit-transition: -webkit-transform 0.3s ease-out, opacity 0.3s ease-in;
+	-moz-transition: -moz-transform 0.3s ease-out, opacity 0.3s ease-in;
+	-o-transition: -o-transform 0.3s ease-out, opacity 0.3s ease-in;
+	transition: transform 0.3s ease-out, opacity 0.3s ease-in;
+}
+
+.leaflet-cluster-spider-leg {
+	/* stroke-dashoffset (duration and function) should match with leaflet-marker-icon transform in order to track it exactly */
+	-webkit-transition: -webkit-stroke-dashoffset 0.3s ease-out, -webkit-stroke-opacity 0.3s ease-in;
+	-moz-transition: -moz-stroke-dashoffset 0.3s ease-out, -moz-stroke-opacity 0.3s ease-in;
+	-o-transition: -o-stroke-dashoffset 0.3s ease-out, -o-stroke-opacity 0.3s ease-in;
+	transition: stroke-dashoffset 0.3s ease-out, stroke-opacity 0.3s ease-in;
+}