feat: Add browser-only launch mode for Kaspersky bypass

- Add `ui.launchBrowser` config option to launch browser directly
- Fix sidecar_manager to support packaged mode paths
- Set BROWSER_MODE env var for backend sidecar management
- Skip Electron window when browser-only mode enabled

Usage: Set `"ui": { "launchBrowser": true }` in config.json
to bypass Kaspersky blocking by using system browser instead.

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

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

client/config.json

@@ -2,6 +2,9 @@
   "apiBaseUrl": "http://localhost:8000/api",
   "uploadTimeout": 600000,
   "appTitle": "Meeting Assistant",
+  "ui": {
+    "launchBrowser": false
+  },
   "whisper": {
     "model": "medium",
     "device": "cpu",

client/src/main.js

@@ -477,6 +477,51 @@ app.whenReady().then(async () => {
   // Load configuration first
   loadConfig();
 
+  const backendConfig = appConfig?.backend || {};
+  const uiConfig = appConfig?.ui || {};
+  const launchBrowser = uiConfig.launchBrowser === true;
+
+  // Browser-only mode: start backend and open browser, no Electron UI
+  if (launchBrowser && backendConfig.embedded) {
+    console.log("=== Browser-Only Mode ===");
+
+    // Set BROWSER_MODE so backend manages sidecar
+    process.env.BROWSER_MODE = "true";
+
+    // Start backend sidecar
+    startBackendSidecar();
+
+    // Wait for backend to be ready
+    const ready = await waitForBackendReady();
+    if (!ready) {
+      const { dialog } = require("electron");
+      dialog.showErrorBox(
+        "Backend Startup Failed",
+        "後端服務啟動失敗。請檢查日誌以獲取詳細信息。"
+      );
+      app.quit();
+      return;
+    }
+
+    // Open browser to login page
+    const host = backendConfig.host || "127.0.0.1";
+    const port = backendConfig.port || 8000;
+    const loginUrl = `http://${host}:${port}/login`;
+
+    console.log(`Opening browser: ${loginUrl}`);
+    await shell.openExternal(loginUrl);
+
+    // Keep app running in background
+    // On macOS, we need to handle dock visibility
+    if (process.platform === "darwin") {
+      app.dock.hide();
+    }
+
+    console.log("Backend running. Close this window or press Ctrl+C to stop.");
+    return;
+  }
+
+  // Standard Electron mode
   // Grant microphone permission automatically
   session.defaultSession.setPermissionRequestHandler((webContents, permission, callback, details) => {
     console.log(`Permission request: ${permission}`, details);
@@ -512,7 +557,6 @@ app.whenReady().then(async () => {
   startBackendSidecar();
 
   // Wait for backend to be ready before creating window
-  const backendConfig = appConfig?.backend || {};
   if (backendConfig.embedded) {
     const ready = await waitForBackendReady();
     if (!ready) {