fix: use github.head_ref for CI_BRANCH in Coveralls integration

For GitHub Actions pull requests, github.ref_name returns the PR reference
(e.g., "293/merge") instead of the actual branch name. The coveralls-jacoco
plugin uses CI_BRANCH to identify the branch in coverage reports. By using
github.head_ref (which provides the branch name for PRs) with github.ref_name
as a fallback (for push events), we ensure the correct branch is reported.

Assisted-By: Claude Code

Author: sonus21

.github/workflows/java-ci.yaml

@@ -467,10 +467,16 @@ jobs:
       - name: Push coverage to Coveralls
         env:
           COVERALLS_REPO_TOKEN: ${{ secrets.COVERALLS_REPO_TOKEN }}
-          CI_BRANCH: ${{ github.ref_name }}
+          CI_BRANCH: ${{ github.head_ref || github.ref_name }}
         run: |
           if [ -z "$COVERALLS_REPO_TOKEN" ]; then
             echo "ERROR: COVERALLS_REPO_TOKEN is not set"
             exit 1
           fi
-          ./gradlew coverallsJacoco
+          ./gradlew coverallsJacoco -i
+          echo "=== Coveralls request payload ==="
+          if [ -f build/coveralls-request.json ]; then
+            cat build/coveralls-request.json | jq . 2>/dev/null || cat build/coveralls-request.json
+          else
+            echo "No coveralls-request.json found"
+          fi