新增 pc-client：畅联 PC 端工程（Electron+React，按确认效果图改造，B-59）

- 基于 openim-electron-demo 改造：工号+密码登录（自研账号服务）、会话列表/聊天窗/通讯录界面重做
- 文字/语音/文件/图片消息、文件拖拽发送、表情面板、一对一语音通话（LiveKit）
- RTC 令牌对接账号服务带鉴权版 /api/rtc_token（Bearer imToken + {room,identity}）
- account-service: CORS Allow-Headers 补 authorization（浏览器/渲染进程跨域调 rtc_token 需要）
- 附本地 mock 账号服务（scripts/mock-account-server.js）与截图联调脚本

pc-client/electron/preload/index.ts

@@ -0,0 +1,118 @@
+import fs from "fs";
+import path from "path";
+import { DataPath, IElectronAPI } from "./../../src/types/globalExpose.d";
+import { contextBridge, ipcRenderer } from "electron";
+import { isProd } from "../utils";
+import "@openim/electron-client-sdk/lib/preload";
+import { Platform } from "@openim/wasm-client-sdk";
+
+const getPlatform = () => {
+  if (process.platform === "darwin") {
+    return Platform.MacOSX;
+  }
+  if (process.platform === "win32") {
+    return Platform.Windows;
+  }
+  return Platform.Linux;
+};
+
+const getDataPath = (key: DataPath) => {
+  switch (key) {
+    case "public":
+      return isProd ? ipcRenderer.sendSync("getDataPath", "public") : "";
+    case "sdkResources":
+      return isProd ? ipcRenderer.sendSync("getDataPath", "sdkResources") : "";
+    case "logsPath":
+      return isProd ? ipcRenderer.sendSync("getDataPath", "logsPath") : "";
+    default:
+      return "";
+  }
+};
+
+const subscribe = (channel: string, callback: (...args: any[]) => void) => {
+  const subscription = (_, ...args) => callback(...args);
+  ipcRenderer.on(channel, subscription);
+  return () => ipcRenderer.removeListener(channel, subscription);
+};
+
+const subscribeOnce = (channel: string, callback: (...args: any[]) => void) => {
+  ipcRenderer.once(channel, (_, ...args) => callback(...args));
+};
+
+const unsubscribeAll = (channel: string) => {
+  ipcRenderer.removeAllListeners(channel);
+};
+
+const ipcInvoke = (channel: string, ...arg: any) => {
+  return ipcRenderer.invoke(channel, ...arg);
+};
+
+const ipcSendSync = (channel: string, ...arg: any) => {
+  return ipcRenderer.sendSync(channel, ...arg);
+};
+
+const getUniqueSavePath = (originalPath: string) => {
+  let counter = 0;
+  let savePath = originalPath;
+  let fileDir = path.dirname(originalPath);
+  let fileName = path.basename(originalPath);
+  let fileExt = path.extname(originalPath);
+  let baseName = path.basename(fileName, fileExt);
+
+  while (fs.existsSync(savePath)) {
+    counter++;
+    fileName = `${baseName}(${counter})${fileExt}`;
+    savePath = path.join(fileDir, fileName);
+  }
+
+  return savePath;
+};
+
+const getFileByPath = async (filePath: string) => {
+  try {
+    const filename = path.basename(filePath);
+    const data = await fs.promises.readFile(filePath);
+    return new File([data], filename);
+  } catch (error) {
+    console.log(error);
+    return null;
+  }
+};
+
+const saveFileToDisk = async ({
+  file,
+  sync,
+}: {
+  file: File;
+  sync?: boolean;
+}): Promise<string> => {
+  const arrayBuffer = await file.arrayBuffer();
+  const saveDir = ipcRenderer.sendSync("getDataPath", "sdkResources");
+  const savePath = path.join(saveDir, file.name);
+  const uniqueSavePath = getUniqueSavePath(savePath);
+  if (!fs.existsSync(saveDir)) {
+    fs.mkdirSync(saveDir, { recursive: true });
+  }
+  if (sync) {
+    await fs.promises.writeFile(uniqueSavePath, Buffer.from(arrayBuffer));
+  } else {
+    fs.promises.writeFile(uniqueSavePath, Buffer.from(arrayBuffer));
+  }
+  return uniqueSavePath;
+};
+
+const Api: IElectronAPI = {
+  getDataPath,
+  getVersion: () => process.version,
+  getPlatform,
+  getSystemVersion: process.getSystemVersion,
+  subscribe,
+  subscribeOnce,
+  unsubscribeAll,
+  ipcInvoke,
+  ipcSendSync,
+  getFileByPath,
+  saveFileToDisk,
+};
+
+contextBridge.exposeInMainWorld("electronAPI", Api);