replace yarn with pnpm

frontend/Dockerfile

@@ -1,19 +1,22 @@
-FROM node:alpine as build
-
+FROM node:alpine as base
+ENV PNPM_HOME="/pnpm"
+ENV PATH="$PNPM_HOME:$PATH"
+RUN corepack enable
+COPY . /app
 WORKDIR /app
-COPY . .
-RUN yarn
-ENV BODY_SIZE_LIMIT=0
-RUN yarn build
-RUN ls -al
 
-FROM node:alpine as production
+FROM base AS prod-deps
+RUN --mount=type=cache,id=pnpm,target=/pnpm/store pnpm install --prod --frozen-lockfile
 
+FROM base AS build
+RUN --mount=type=cache,id=pnpm,target=/pnpm/store pnpm install --frozen-lockfile
 ENV BODY_SIZE_LIMIT=0
+RUN pnpm run build
 
+FROM base
 WORKDIR /app
-COPY --from=build /app/package.json ./
-COPY --from=build /app/build/ ./
-RUN yarn --production
+ENV BODY_SIZE_LIMIT=0
+COPY --from=prod-deps /app/node_modules /app/node_modules
+COPY --from=build /app/build ./
 EXPOSE 3000
 CMD [ "node",  "index.js"]