feat(ci): add Codecov upload to release workflow (#605)

* feat(ci): add Codecov upload to release workflow

Add upload-coverage job that runs after Unity tests complete,
uploading coverage reports to Codecov with util and ui flags.
This ensures coverage is tracked for releases, not just PRs.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
Signed-off-by: JasonXuDeveloper - 傑 <jason@xgamedev.net>

* fix(ci): set fail_ci_if_error to true for consistency

Match pr-tests.yml behavior where Codecov upload failures
will fail the workflow.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
Signed-off-by: JasonXuDeveloper - 傑 <jason@xgamedev.net>

---------

Signed-off-by: JasonXuDeveloper - 傑 <jason@xgamedev.net>
Co-authored-by: Claude Opus 4.5 <noreply@anthropic.com>

Author: JasonXuDeveloper

.github/workflows/release.yml

@@ -160,6 +160,47 @@ jobs:
     uses: ./.github/workflows/unity-tests.yml
     secrets: inherit
 
+  upload-coverage:
+    name: Upload Coverage
+    needs: run-tests
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+
+      - name: Download coverage artifacts
+        uses: actions/download-artifact@v4
+        with:
+          name: Coverage-results-2022.3.55f1
+          path: coverage
+
+      - name: List coverage files
+        run: |
+          echo "Coverage directory structure:"
+          find coverage -type f -name "*.xml" 2>/dev/null || echo "No XML files found"
+
+      - name: Upload coverage to Codecov (util package)
+        uses: codecov/codecov-action@v4
+        with:
+          token: ${{ secrets.CODECOV_TOKEN }}
+          files: coverage/**/TestCoverageResults*.xml
+          flags: util
+          name: jengine-util
+          fail_ci_if_error: true
+          verbose: true
+
+      - name: Upload coverage to Codecov (ui package)
+        uses: codecov/codecov-action@v4
+        with:
+          token: ${{ secrets.CODECOV_TOKEN }}
+          files: coverage/**/TestCoverageResults*.xml
+          flags: ui
+          name: jengine-ui
+          fail_ci_if_error: true
+          verbose: true
+
   prepare-release:
     name: Prepare Release
     needs: [validate, run-tests]