Modify CI workflow for concurrency and port management

Updated concurrency group naming and added a step to ensure Metro port is free before starting the package manager.

Author: wcandillon

.github/workflows/ci.yml

@@ -12,7 +12,7 @@ on:
   workflow_dispatch:
 
 concurrency:
-  group: ${{ github.ref }}
+  group: ci-${{ github.event.pull_request.number || github.ref }}
   cancel-in-progress: true
 
 jobs:
@@ -37,6 +37,10 @@ jobs:
         working-directory: apps/example/ios
         run: pod install
 
+      - name: Ensure Metro port is free
+        run: |
+          lsof -ti :8081 | xargs -r kill -9 || true
+
       - name: Start Package Manager
         working-directory: apps/example
         run: E2E=true yarn start &