chore: auto-trigger create-github-release on release PR merge

Change workflow to automatically run when release PRs are merged.

- Trigger on pull_request closed event instead of workflow_dispatch
- Only run if PR was merged and title contains 'Release'
- Support both main and version branches (e.g., 5.3-main)
- Use PR base branch for checkout instead of manual input

Author: nan-li

.github/workflows/create-github-release.yml

@@ -1,16 +1,15 @@
 name: Create GitHub Release
 
 # This workflow creates a GitHub release in iOS-SDK and attaches the built zip files.
-# Run this AFTER the release PR has been merged.
+# Runs automatically when a release PR is merged.
 
 on:
-  workflow_dispatch:
-    inputs:
-      ref:
-        description: 'Branch or commit SHA to run on (e.g., main, 5.3-main)'
-        type: string
-        required: false
-        default: 'main'
+  pull_request:
+    types:
+      - closed
+    branches:
+      - main
+      - '*-main'  # Matches version branches like 5.3-main
 
 permissions:
   contents: write
@@ -23,14 +22,17 @@ concurrency:
 jobs:
   # Step 1: Extract version from podspec
   get-version:
+    if: |
+      github.event.pull_request.merged == true &&
+      contains(github.event.pull_request.title, 'Release')
     runs-on: ubuntu-latest
     outputs:
       version: ${{ steps.extract_version.outputs.version }}
     steps:
       - name: Checkout OneSignal-iOS-SDK
         uses: actions/checkout@v4
         with:
-          ref: ${{ github.event.inputs.ref }}
+          ref: ${{ github.event.pull_request.base.ref }}
 
       - name: Extract release version from podspec
         id: extract_version
@@ -59,7 +61,7 @@ jobs:
       - name: Checkout OneSignal-iOS-SDK
         uses: actions/checkout@v4
         with:
-          ref: ${{ github.event.inputs.ref }}
+          ref: ${{ github.event.pull_request.base.ref }}
 
       - name: 📋 Display Configuration
         run: |