add electron e2e harness and regression coverage (#697)

.github/workflows/electron-e2e.yml

@@ -0,0 +1,67 @@
+name: Electron E2E
+
+on:
+  workflow_dispatch:
+  pull_request:
+    branches:
+      - main
+  push:
+    branches:
+      - main
+
+jobs:
+  electron-e2e:
+    name: Electron E2E (${{ matrix.os }})
+    runs-on: ${{ matrix.os }}
+    timeout-minutes: 20
+    strategy:
+      fail-fast: false
+      matrix:
+        os:
+          - ubuntu-latest
+          - macos-latest
+          - windows-latest
+    env:
+      CI: 'true'
+
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v6
+
+      - name: Setup pnpm
+        uses: pnpm/action-setup@v4
+
+      - name: Setup Node.js
+        uses: actions/setup-node@v6
+        with:
+          node-version: '24'
+          cache: 'pnpm'
+
+      - name: Install dependencies
+        run: pnpm install --frozen-lockfile
+
+      - name: Rebuild Electron binary
+        run: pnpm rebuild electron
+
+      - name: Run Electron E2E on Linux
+        if: runner.os == 'Linux'
+        run: xvfb-run -a pnpm run test:e2e
+
+      - name: Run Electron E2E on macOS
+        if: runner.os == 'macOS'
+        run: pnpm run test:e2e
+
+      - name: Run Electron E2E on Windows
+        if: runner.os == 'Windows'
+        run: pnpm run test:e2e
+
+      - name: Upload Playwright artifacts
+        if: always()
+        uses: actions/upload-artifact@v4
+        with:
+          name: playwright-artifacts-${{ matrix.os }}
+          path: |
+            playwright-report
+            test-results
+          if-no-files-found: warn
+          retention-days: 7