Add Electron E2E harness launcher

package.json

@@ -19,7 +19,7 @@
     "test:render-server": "node --test server/server.smoke.test.cjs",
     "test:render-server:e2e": "node --test server/render.e2e.test.cjs",
     "test:render-desktop": "tsc -p tsconfig.electron.json && node scripts/verify-desktop-render.cjs",
-    "test:capture-fidelity": "tsc -p tsconfig.electron.json && electron scripts/verify-capture-fidelity.cjs",
+    "test:capture-fidelity": "tsc -p tsconfig.electron.json && node scripts/run-electron-harness.cjs scripts/verify-capture-fidelity.cjs",
     "stage:ffmpeg": "node scripts/stage-ffmpeg.cjs"
   },
   "dependencies": {