Initial commit: Visigine (Vite client + Express/SQLite backend)

Container-ready via docker/ compose (frontend nginx + backend Node). Compose adjusted for Coolify on the prod server: frontend uses expose:80 (no host binding — host 8080 is taken by the Coolify proxy; Traefik routes visigine.de), backend ALLOWED_ORIGINS=https://visigine.de. Secrets stay in server/.env (git-ignored); see server/.env.example.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

docker/frontend.Dockerfile

@@ -0,0 +1,23 @@
+# Visigine frontend — multi-stage: build React with Vite, then serve with nginx.
+# Build context is the repo root (see docker-compose.yml).
+
+# ── stage 1: build ────────────────────────────────────────────────
+FROM node:20-alpine AS build
+WORKDIR /app
+
+COPY package.json package-lock.json* ./
+RUN npm ci
+
+COPY index.html vite.config.js eslint.config.js ./
+COPY src ./src
+COPY public ./public
+
+RUN npm run build
+
+# ── stage 2: runtime ──────────────────────────────────────────────
+FROM nginx:1.27-alpine AS runtime
+
+COPY --from=build /app/dist /usr/share/nginx/html
+COPY docker/nginx.conf /etc/nginx/conf.d/default.conf
+
+EXPOSE 80