Code coverage pre-QA push.

.github/workflows/ci.yml

@@ -161,6 +161,7 @@ jobs:
     env:
       NODE_TLS_REJECT_UNAUTHORIZED: 0
       AZURE_SUBSCRIPTION_ID: ${{ secrets.AZURE_SUBSCRIPTION_ID }}
+      COVERAGE: "true"
     strategy:
       fail-fast: false
       matrix:
@@ -219,6 +220,13 @@ jobs:
           name: blob-report-${{ matrix.shardIndex }}
           path: blob-report
           retention-days: 1
+      - name: Upload coverage data
+        if: ${{ !cancelled() }}
+        uses: actions/upload-artifact@v4
+        with:
+          name: coverage-data-${{ matrix.shardIndex }}
+          path: .nyc_output
+          retention-days: 1
 
   merge-playwright-reports:
     name: "Merge Playwright Reports"
@@ -251,3 +259,39 @@ jobs:
           name: html-report--attempt-${{ github.run_attempt }}
           path: playwright-report
           retention-days: 14
+
+  merge-coverage:
+    name: "Merge Code Coverage"
+    if: ${{ !cancelled() }}
+    needs: [playwright-tests]
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions/setup-node@v4
+        with:
+          node-version: 18
+      - name: Install dependencies
+        run: npm ci
+
+      - name: Download coverage data from all shards
+        uses: actions/download-artifact@v4
+        with:
+          path: all-coverage
+          pattern: coverage-data-*
+          merge-multiple: true
+
+      - name: Merge coverage data
+        run: |
+          mkdir -p .nyc_output
+          cp all-coverage/*.json .nyc_output/ 2>/dev/null || true
+          npx nyc merge .nyc_output .nyc_output/merged-coverage.json
+
+      - name: Generate coverage report
+        run: npx nyc report --temp-dir .nyc_output --report-dir coverage-e2e --reporter text --reporter text-summary --reporter lcov --reporter html
+
+      - name: Upload coverage report
+        uses: actions/upload-artifact@v4
+        with:
+          name: coverage-report--attempt-${{ github.run_attempt }}
+          path: coverage-e2e
+          retention-days: 14