Fix Docker build - Add PORT environment variable

- Add PORT=3000 to both Dockerfile and docker-compose.yml
- Ensure proper file ownership in standalone build
- Fix potential 404 routing issues

Co-Authored-By: Claude <noreply@anthropic.com>

Dockerfile

@@ -24,6 +24,8 @@ WORKDIR /app
 
 # Set environment to production
 ENV NODE_ENV=production
+ENV PORT=3000
+ENV HOSTNAME="0.0.0.0"
 
 # Create a non-root user
 RUN addgroup --system --gid 1001 nodejs
@@ -31,8 +33,8 @@ RUN adduser --system --uid 1001 nextjs
 
 # Copy necessary files from builder
 COPY --from=builder /app/public ./public
-COPY --from=builder /app/.next/standalone ./
-COPY --from=builder /app/.next/static ./.next/static
+COPY --from=builder --chown=nextjs:nodejs /app/.next/standalone ./
+COPY --from=builder --chown=nextjs:nodejs /app/.next/static ./.next/static
 
 # Change ownership to nextjs user
 RUN chown -R nextjs:nodejs /app
@@ -43,8 +45,5 @@ USER nextjs
 # Expose port 3000
 EXPOSE 3000
 
-# Set hostname
-ENV HOSTNAME="0.0.0.0"
-
 # Start the application
 CMD ["node", "server.js"]