Implmement coverage upload as callable workflow

.github/workflows/upload_coverage.yml

@@ -0,0 +1,80 @@
+name: Upload coverage
+
+on:
+  workflow_call:
+    inputs:
+      fail-on-coverage-error:
+        required: false
+        type: boolean
+        default: true
+        description: Fail if codecov action fails.
+      artifact-pattern:
+        required: false
+        type: string
+        default: covreport-*
+        description: >
+          glob pattern to the artifacts that should be downloaded for coverage reports.
+          This should match the `name` you used for the `upload-artifact` step in the
+          job that generates the coverage reports.
+          (*This default matches the name in test-pyrepo.yml*)
+    secrets:
+      codecov_token:
+        required: false
+        description: Token for codecov-action.
+
+jobs:
+  upload_coverage:
+    name: Upload coverage
+    runs-on: ubuntu-latest
+    steps:
+
+      - name: Checkout ${{ github.repository }}
+        uses: actions/checkout@v5
+
+      - name: Install the latest version of uv
+        uses: astral-sh/setup-uv@v6
+        with:
+          version: "latest"
+          python-version: '3.12'
+          activate-environment: true
+
+      - name: Install coverage
+        run: uv pip install coverage
+
+      - name: Download coverage data
+        uses: actions/download-artifact@v5
+        with:
+          pattern: ${{ inputs.artifact-pattern }}
+          path: covreports
+          merge-multiple: true
+
+      - name: Combine coverage data
+        run: |
+          REPO_NAME="${GITHUB_REPOSITORY##*/}"
+          echo "[paths]" > ci_coveragerc
+          echo "source =" >> ci_coveragerc
+          # if src exists, add it to the pathmap
+          if [ -d "src" ]; then
+            echo "    src/" >> ci_coveragerc
+            echo "    D:\\a\\$REPO_NAME\\$REPO_NAME\\src" >> ci_coveragerc
+            echo "    /home/runner/work/$REPO_NAME/$REPO_NAME/src" >> ci_coveragerc
+            echo "    /Users/runner/work/$REPO_NAME/$REPO_NAME/src" >> ci_coveragerc
+          else
+            echo "    ${GITHUB_WORKSPACE}" >> ci_coveragerc
+            echo "    D:\\a\\$REPO_NAME\\$REPO_NAME" >> ci_coveragerc
+            echo "    /home/runner/work/$REPO_NAME/$REPO_NAME" >> ci_coveragerc
+            echo "    /Users/runner/work/$REPO_NAME/$REPO_NAME" >> ci_coveragerc
+          fi
+          echo "    */site-packages/" >> ci_coveragerc
+          cat ci_coveragerc
+          python -Im coverage combine --rcfile=ci_coveragerc covreports
+          python -Im coverage xml -o coverage.xml
+          python -Im coverage report
+          python -Im coverage report --format=markdown --skip-empty --skip-covered >> $GITHUB_STEP_SUMMARY
+
+      - name: Upload to codecov
+        uses: codecov/codecov-action@v5
+        with:
+          fail_ci_if_error: ${{ inputs.fail-on-coverage-error }}
+          verbose: true
+          token: ${{ secrets.CODECOV_TOKEN }}