configure dockerfile for pnpm

Dockerfile

@@ -1,12 +1,21 @@
-FROM node:20.16.0-alpine3.20 AS runtime
-WORKDIR /app
+FROM node:20.16.0-alpine3.20 AS base
 
+ENV PNPM_HOME="/pnpm"
+ENV PATH="$PNPM_HOME:$PATH"
+RUN corepack enable
+
+WORKDIR /app
 COPY . .
 
-RUN pnpm install
+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
 RUN pnpm run build
 
-ENV HOST=0.0.0.0
-ENV PORT=4321
-EXPOSE 4321
-CMD node ./dist/server/entry.mjs
+FROM base
+COPY --from=prod-deps /app/node_modules /app/node_modules
+COPY --from=build /app/dist /app/dist
+EXPOSE 8000
+CMD [ "pnpm", "start" ]