feat(ci): add concurrency control to cancel stale builds

Cancel in-progress workflow runs when a newer one is triggered on the same ref.
This prevents wasting CI resources on outdated builds and ensures only the
latest code is built and deployed.

Concurrency group: workflow name + git ref (branch/tag)
Behavior: Automatically cancels older runs when new one starts

Author: pythoninthegrass

.github/workflows/build-ios-app.yml

@@ -6,6 +6,11 @@ on:
   # Manual trigger for testing
   workflow_dispatch:
 
+# Cancel in-progress builds when a newer one is triggered
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
 jobs:
   build:
     runs-on: macos-latest