ci: trigger ios-flow on pull_request events

ios-flow was only triggered on manual dispatch with platform=ios.
Also trigger it on every PR so iOS is validated alongside Android.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Co-authored-by: Srinivasan Sekar <srinivasan.sekar1990@gmail.com>

Author: saikrishna321

.github/workflows/layer3-branch-test.yml

@@ -75,7 +75,7 @@ jobs:
   ios-flow:
     name: iOS — YAML flow
     runs-on: macos-14
-    if: github.event_name == 'workflow_dispatch' && inputs.platform == 'ios'
+    if: github.event_name == 'pull_request' || (github.event_name == 'workflow_dispatch' && inputs.platform == 'ios')
 
     steps:
       - uses: actions/checkout@v4