debug(service-party-app): 添加 TSS 进程详细调试日志

- 输出二进制文件路径和存在性检查
- 输出传递给 TSS 的参与者列表 JSON
- 输出完整的命令行参数
- 收集并输出 stderr 内容
- 帮助诊断 TSS 进程 exit code 1 问题

Generated with Claude Code

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

backend/mpc-system/services/service-party-app/electron/modules/tss-handler.ts

@@ -198,12 +198,16 @@ export class TSSHandler extends EventEmitter {
     return new Promise((resolve, reject) => {
       try {
         const binaryPath = this.getTSSBinaryPath();
+        console.log(`[TSS] Binary path: ${binaryPath}`);
+        console.log(`[TSS] Binary exists: ${fs.existsSync(binaryPath)}`);
 
         // 构建参与者列表 JSON
         const participantsJson = JSON.stringify(participants);
+        console.log(`[TSS] Participants: ${participantsJson}`);
+        console.log(`[TSS] partyIndex=${partyIndex}, threshold=${threshold.t}-of-${threshold.n}`);
 
         // 启动 TSS 子进程
-        this.tssProcess = spawn(binaryPath, [
+        const args = [
           'keygen',
           '--session-id', sessionId,
           '--party-id', partyId,
@@ -212,9 +216,13 @@ export class TSSHandler extends EventEmitter {
           '--threshold-n', threshold.n.toString(),
           '--participants', participantsJson,
           '--password', encryptionPassword,
-        ]);
+        ];
+        console.log(`[TSS] Spawning: ${binaryPath} ${args.join(' ')}`);
+
+        this.tssProcess = spawn(binaryPath, args);
 
         let resultData = '';
+        let stderrData = '';
 
         // 如果没有预订阅，现在订阅消息
         // 如果已经预订阅，消息监听器已经注册，不需要重复注册
@@ -254,7 +262,9 @@ export class TSSHandler extends EventEmitter {
 
         // 处理标准错误
         this.tssProcess.stderr?.on('data', (data: Buffer) => {
-          console.error('[TSS Error]', data.toString());
+          const errorText = data.toString();
+          stderrData += errorText;
+          console.error('[TSS stderr]', errorText);
         });
 
         // 处理进程退出
@@ -289,7 +299,9 @@ export class TSSHandler extends EventEmitter {
               reject(new Error(`Failed to parse keygen result: ${e}`));
             }
           } else {
-            reject(new Error(`Keygen process exited with code ${code}`));
+            const errorMsg = stderrData.trim() || `Keygen process exited with code ${code}`;
+            console.error(`[TSS] Process failed: code=${code}, stderr=${stderrData}`);
+            reject(new Error(errorMsg));
           }
         });