Fix: single-stage build to avoid pnpm symlink issues

Dockerfile

@@ -1,9 +1,9 @@
-FROM node:20-slim AS base
+FROM node:20-slim
+
 RUN npm install -g pnpm
 
 WORKDIR /app
 
-FROM base AS builder
 COPY package.json pnpm-workspace.yaml pnpm-lock.yaml ./
 COPY packages/shared/package.json ./packages/shared/
 COPY apps/server/package.json ./apps/server/
@@ -17,15 +17,6 @@ WORKDIR /app/apps/server
 RUN pnpm db:generate
 RUN pnpm build
 
-FROM node:20-slim AS runner
-RUN npm install -g pnpm
-
-WORKDIR /app
-
-COPY --from=builder /app/apps/server/dist ./dist
-COPY --from=builder /app/apps/server/node_modules ./node_modules
-COPY --from=builder /app/apps/server/prisma ./prisma
-
 ENV NODE_ENV=production
 ENV PORT=7860
 EXPOSE 7860