Initial SvelteKit frontend port of windwiderstand.de

Full parity with Astro site: content rows, post/tag routes, pagination,
event badges + OSM map, comments, Live-Search via /api/search-index,
CMS image proxy, RSS, sitemap.

Deploy: Dockerfile + docker-compose.prod.yml + Gitea Actions workflow
to build + push to git.pm86.de registry and ssh-deploy to Contabo.

static/safari-pinned-tab.svg

@@ -0,0 +1,10 @@
+<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 32 32" fill="none">
+  <path
+    d="M6 8l4 16 4-10 4 10 4-16"
+    stroke="currentColor"
+    stroke-width="2.5"
+    stroke-linecap="round"
+    stroke-linejoin="round"
+    fill="none"
+  />
+</svg>