fix(mining-service): 添加Dockerfile构建验证步骤

backend/services/mining-service/Dockerfile

@@ -14,7 +14,7 @@ RUN npm ci
 RUN DATABASE_URL="postgresql://user:pass@localhost:5432/db" npx prisma generate
 
 COPY src ./src
-RUN npm run build
+RUN npm run build && ls -la dist/ && test -f dist/main.js && echo "Build successful: dist/main.js exists"
 
 # 阶段2: 生产运行
 FROM node:20-alpine AS runner
@@ -37,6 +37,7 @@ COPY --chown=nestjs:nodejs prisma ./prisma/
 RUN DATABASE_URL="postgresql://user:pass@localhost:5432/db" npx prisma generate
 
 COPY --chown=nestjs:nodejs --from=builder /app/dist ./dist
+RUN ls -la dist/ && test -f dist/main.js && echo "Copy successful: dist/main.js exists"
 
 RUN printf '#!/bin/sh\nset -e\necho "Running database migrations..."\nnpx prisma migrate deploy\necho "Running database seed..."\nnpx prisma db seed || echo "Seed skipped or already applied"\necho "Starting application..."\nexec node dist/main.js\n' > /app/start.sh && chmod +x /app/start.sh