remove unused SonarCloud job (CodeQL already covers this)

Author: nikolay-e

.github/workflows/ci.yml

@@ -294,49 +294,3 @@ jobs:
 
       - name: Check import contracts
         run: lint-imports
-
-  # ============================================================================
-  # SonarCloud Quality Gate
-  # Evidence: Complexity/duplication metrics correlate with defect density
-  # ============================================================================
-  sonarcloud:
-    name: SonarCloud Analysis
-    runs-on: ubuntu-latest
-    needs: test
-    if: github.event_name == 'pull_request' || github.ref == 'refs/heads/main'
-
-    steps:
-      - uses: actions/checkout@v6
-        with:
-          fetch-depth: 0
-
-      - name: Download coverage reports
-        uses: actions/download-artifact@v7
-        with:
-          name: coverage-report
-          path: .
-
-      - name: Verify coverage files exist
-        run: |
-          echo "=== Checking for coverage files ==="
-          ls -lh coverage.xml test-results.xml || true
-          echo "=== Coverage.xml source paths ==="
-          head -10 coverage.xml || true
-
-      - name: Create sonar-project.properties
-        run: |
-          cat > sonar-project.properties <<EOF
-          sonar.projectKey=nikolay-e_treemapper
-          sonar.organization=nikolay-e
-          sonar.sources=src/treemapper
-          sonar.tests=tests
-          sonar.python.coverage.reportPaths=coverage.xml
-          sonar.python.xunit.reportPath=test-results.xml
-          sonar.python.version=3.10,3.11,3.12,3.13
-          EOF
-
-      - name: SonarCloud Scan
-        uses: SonarSource/sonarcloud-github-action@ba3875ecf642b2129de2b589510c81a8b53dbf4e  # master
-        env:
-          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
-          SONAR_TOKEN: ${{ secrets.SONAR_TOKEN }}