add new lesson mode and started code refraction

client/Dockerfile

@@ -1,7 +1,10 @@
 FROM node:24-alpine AS dev-stage
 WORKDIR /app
+
 COPY package*.json ./
-RUN npm install
+
+RUN npm ci
+
 COPY . .
 EXPOSE 5173
 CMD ["npm", "run", "dev", "--", "--host"]
@@ -10,8 +13,3 @@ FROM dev-stage AS build-stage
 ARG VITE_API_URL
 ENV VITE_API_URL=$VITE_API_URL
 RUN npm run build
-
-FROM nginx:stable-alpine AS production-stage
-COPY --from=build-stage /app/dist /usr/share/nginx/html
-EXPOSE 80
-CMD ["nginx", "-g", "daemon off;"]