fix(mpc-service): 安装 OpenSSL 1.1 修复 Prisma 引擎加载失败

错误: libssl.so.1.1: No such file or directory
解决: 在 production stage 安装 openssl1.1-compat

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

backend/services/mpc-service/Dockerfile

@@ -30,6 +30,9 @@ FROM node:20-alpine
 
 WORKDIR /app
 
+# Install OpenSSL 1.1 for Prisma
+RUN apk add --no-cache openssl1.1-compat
+
 # Install production dependencies only
 COPY package*.json ./
 RUN npm ci --only=production