Simplify pub.dev publishing workflow using official action

Replace custom publishing implementation with dart-lang/setup-dart's reusable workflow. This removes the need for manual credential management and version checking while adding proper semver tag filtering.

Author: xvrh

.github/workflows/publish-on-pub.yaml

@@ -2,28 +2,9 @@ name: Publish package to pub.dev
 on:
   push:
     tags:
-      - v*
+      - 'v[0-9]+.[0-9]+.[0-9]+*'
 jobs:
-  build:
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v4
-      - uses: subosito/flutter-action@v2
-        with:
-          channel: 'stable'
-      - run: flutter pub get
-      - run: flutter pub run tool/publish/check_version.dart ${GITHUB_REF}
-      - name: Setup credentials
-        run: |
-          mkdir -p $XDG_CONFIG_HOME/dart
-          cat <<EOF > $XDG_CONFIG_HOME/dart/pub-credentials.json
-          {
-            "accessToken":"${{ secrets.OAUTH_ACCESS_TOKEN }}",
-            "refreshToken":"${{ secrets.OAUTH_REFRESH_TOKEN }}",
-            "tokenEndpoint":"https://accounts.google.com/o/oauth2/token",
-            "scopes": [ "openid", "https://www.googleapis.com/auth/userinfo.email" ],
-            "expiration": 1691492965565
-          }
-          EOF
-      - name: Publish package
-        run: flutter pub publish --force
+  publish:
+    permissions:
+      id-token: write
+    uses: dart-lang/setup-dart/.github/workflows/publish.yml@v1