feat(computer): improve Linux headless display quality

- Increase Xvfb resolution from default 1920x1080 to 2560x1440x24
- Add fluxbox window manager for proper window decorations
- Install GTK themes (adwaita, gnome-themes-extra) for native UI styling
- Add Noto CJK fonts for proper CJK character rendering
- Add dbus-x11 for GTK application support

Author: quanru

.github/workflows/computer-electron-demo.yaml

@@ -17,7 +17,6 @@ on:
   push:
     branches:
       - main
-      - feat/computer-electron-demo
     paths:
       - 'computer/electron-demo/**'
       - '.github/workflows/computer-electron-demo.yaml'
@@ -63,7 +62,12 @@ jobs:
             libnotify4 \
             libsecret-1-0 \
             libxss1 \
-            xdg-utils
+            xdg-utils \
+            fluxbox \
+            adwaita-icon-theme \
+            gnome-themes-extra \
+            fonts-noto-cjk \
+            dbus-x11
 
       - name: Download Obsidian AppImage
         working-directory: computer/electron-demo

computer/electron-demo/demo.ts

@@ -103,8 +103,20 @@ function launchApp(
     aiActionContext:
       'You are interacting with Obsidian, a note-taking desktop application. ' +
       'If any dialog or popup appears, dismiss it by clicking the close button or pressing Escape.',
+    xvfbResolution: '2560x1440x24',
   });
 
+  // --- Start window manager for proper window decorations on headless Linux ---
+  if (process.platform === 'linux' && process.env.DISPLAY) {
+    const fluxbox = spawn('fluxbox', [], {
+      detached: true,
+      stdio: 'ignore',
+    });
+    fluxbox.unref();
+    console.log('Fluxbox window manager started');
+    await sleep(1000);
+  }
+
   // --- Launch Obsidian AFTER Xvfb is ready (DISPLAY is now set) ---
   const child = launchApp(binaryPath, VAULT_DIR);
   console.log(`Obsidian launched (pid: ${child.pid})`);