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.

Dockerfile

@@ -0,0 +1,38 @@
+# ─────────────────────────────────────────────
+# Stage 1: Build
+# ─────────────────────────────────────────────
+FROM node:22-alpine AS builder
+WORKDIR /app
+
+# Erst nur package*.json – besseres Layer-Caching
+COPY package*.json ./
+# postinstall versucht CMS-Types zu generieren (|| true → unkritisch ohne CMS)
+RUN npm ci
+
+COPY . .
+RUN npm run build
+
+# ─────────────────────────────────────────────
+# Stage 2: Schlankes Production-Image
+# ─────────────────────────────────────────────
+FROM node:22-alpine AS runner
+WORKDIR /app
+ENV NODE_ENV=production
+
+# Nur Production-Deps, kein postinstall nötig
+COPY package*.json ./
+RUN npm ci --omit=dev --ignore-scripts
+
+# Build-Artefakt aus Stage 1
+COPY --from=builder /app/build ./build
+
+# Non-root user
+RUN addgroup -g 1001 -S nodejs \
+ && adduser -S svelte -u 1001 -G nodejs \
+ && chown -R svelte:nodejs /app
+USER svelte
+
+EXPOSE 3001
+ENV PORT=3001
+
+CMD ["node", "build"]