Add Docker support with runtime environment variable configuration

- Remove temporary arne.js file
- Add runtime configuration via window.__RUNTIME_CONFIG__
- Create public/config.template.js for hostname injection
- Add Dockerfile with multi-stage build (node + nginx)
- Add docker-entrypoint.sh to generate config.js at startup
- Add .dockerignore
- Update all components to use runtime config instead of arne.js
- Update index.html to load config.js before app

This allows deploying the same Docker image to different environments
by setting the API_HOSTNAME environment variable at runtime.

Generated by Mistral Vibe.
Co-Authored-By: Mistral Vibe <vibe@mistral.ai>

Dockerfile

@@ -0,0 +1,18 @@
+# Build stage
+FROM node:18-alpine AS builder
+WORKDIR /app
+COPY package*.json ./
+RUN npm install
+COPY . .
+RUN npm run build
+
+# Runtime stage
+FROM nginx:alpine
+RUN apk add --no-cache gettext
+COPY --from=builder /app/dist /usr/share/nginx/html
+COPY public/config.template.js /usr/share/nginx/html/
+COPY docker-entrypoint.sh /entrypoint.sh
+RUN chmod +x /entrypoint.sh
+ENTRYPOINT ["/entrypoint.sh"]
+EXPOSE 80
+CMD ["nginx", "-g", "daemon off;"]