fix(service-party-app): 延迟加载 proto 定义避免启动时崩溃

将 proto 文件加载改为延迟加载模式，在 connect() 时才加载，
避免模块加载时 app.isPackaged 还未准备好导致的路径错误。

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

backend/mpc-system/services/service-party-app/electron/modules/grpc-client.ts

@@ -4,18 +4,6 @@ import * as path from 'path';
 import { EventEmitter } from 'events';
 import { app } from 'electron';
 
-// Proto 文件路径 - 在打包后需要从 app.asar.unpacked 或 resources 目录加载
-function getProtoPath(): string {
-  // 开发环境
-  if (!app.isPackaged) {
-    return path.join(__dirname, '../../proto/message_router.proto');
-  }
-  // 生产环境 - proto 文件需要解包
-  return path.join(process.resourcesPath, 'proto/message_router.proto');
-}
-
-const PROTO_PATH = getProtoPath();
-
 // 定义 proto 包结构类型
 interface ProtoPackage {
   mpc?: {
@@ -27,14 +15,34 @@ interface ProtoPackage {
   };
 }
 
-// 加载 Proto 定义
+// 延迟加载的 Proto 定义
-const packageDefinition = protoLoader.loadSync(PROTO_PATH, {
+let packageDefinition: protoLoader.PackageDefinition | null = null;
-  keepCase: true,
+
-  longs: String,
+// Proto 文件路径 - 在打包后需要从 app.asar.unpacked 或 resources 目录加载
-  enums: String,
+function getProtoPath(): string {
-  defaults: true,
+  // 开发环境
-  oneofs: true,
+  if (!app.isPackaged) {
-});
+    return path.join(__dirname, '../../proto/message_router.proto');
+  }
+  // 生产环境 - proto 文件需要解包
+  return path.join(process.resourcesPath, 'proto/message_router.proto');
+}
+
+// 延迟加载 Proto 定义
+function loadProtoDefinition(): protoLoader.PackageDefinition {
+  if (!packageDefinition) {
+    const protoPath = getProtoPath();
+    console.log('Loading proto from:', protoPath);
+    packageDefinition = protoLoader.loadSync(protoPath, {
+      keepCase: true,
+      longs: String,
+      enums: String,
+      defaults: true,
+      oneofs: true,
+    });
+  }
+  return packageDefinition;
+}
 
 interface SessionInfo {
   sessionId: string;
@@ -116,7 +124,8 @@ export class GrpcClient extends EventEmitter {
    */
   async connect(address: string, useTLS?: boolean): Promise<void> {
     return new Promise((resolve, reject) => {
-      const proto = grpc.loadPackageDefinition(packageDefinition) as ProtoPackage;
+      const definition = loadProtoDefinition();
+      const proto = grpc.loadPackageDefinition(definition) as ProtoPackage;
       const MessageRouter = proto.mpc?.router?.v1?.MessageRouter;
 
       if (!MessageRouter) {