Add release validation workflow for GitHub Actions

Author: pratikPSB

.github/workflows/release_validation.yml

@@ -0,0 +1,37 @@
+name: Release Validation
+
+on:
+  push:
+    tags:
+      - '[0-9]+.[0-9]+.[0-9]+*'
+
+jobs:
+  validate:
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Set up Flutter (latest stable)
+        uses: subosito/flutter-action@v2
+        with:
+          channel: stable
+
+      - name: Install dependencies
+        run: flutter pub get
+
+      - name: Validate version matches tag
+        run: |
+          TAG=${GITHUB_REF#refs/tags/}
+          PUB_VERSION=$(grep '^version:' pubspec.yaml | awk '{print $2}')
+          if [ "$TAG" != "$PUB_VERSION" ]; then
+            echo "Tag ($TAG) does not match pubspec version ($PUB_VERSION)"
+            exit 1
+          fi
+
+      - name: Ensure CHANGELOG updated
+        run: |
+          grep -q "$TAG" CHANGELOG.md || (echo "CHANGELOG missing version $TAG" && exit 1)
+
+      - name: Dry-run pub publish
+        run: dart pub publish --dry-run