Fix healthchecks: install curl in backend and frontend images

frontend/Dockerfile

@@ -0,0 +1,20 @@
+FROM node:22-alpine AS build
+
+WORKDIR /app
+
+COPY package*.json ./
+RUN npm ci
+
+COPY . .
+
+RUN npm run build
+
+FROM nginx:alpine
+RUN apt-get update && apt-get install -y curl && rm -rf /var/lib/apt/lists/*
+
+COPY --from=build /app/dist /usr/share/nginx/html
+COPY nginx.conf /etc/nginx/conf.d/default.conf
+
+EXPOSE 80
+
+CMD ["nginx", "-g", "daemon off;"]