fix(vercel): serialize yarn install to prevent date-fns extraction failure

Add `--child-concurrency 1` and `--network-timeout 600000` to Vercel install command.

.gitignore

@@ -175,4 +175,5 @@ scripts/upload-selectors-smoke-report.json
 scripts/upload-selectors-smoke-snapshots/
 
 # Android build artifacts
-android/app/build/
+android/app/build/
+.vercel

vercel.json

@@ -2,6 +2,7 @@
   "rewrites": [
     { "source": "/(.*)", "destination": "/index.html" }
   ],
+  "installCommand": "yarn install --network-timeout 600000 --child-concurrency 1",
   "buildCommand": "yarn build",
   "outputDirectory": "build",
   "framework": "vite"