fix: add coverage instrumentation env var and fail_ci_if_error to test results upload

- Add VSC_JUPYTER_INSTRUMENT_CODE_FOR_COVERAGE env var to test step to enable coverage generation
- Add fail_ci_if_error: false to test results upload for consistency with coverage upload

Addresses CodeRabbit automated review feedback on PR #35

Author: devin-ai-integration[bot]

.github/workflows/ci.yml

@@ -91,6 +91,8 @@ jobs:
 
       - name: Run tests
         run: npm test
+        env:
+          VSC_JUPYTER_INSTRUMENT_CODE_FOR_COVERAGE: true
 
       - name: Upload coverage to Codecov
         uses: codecov/codecov-action@v5
@@ -105,6 +107,7 @@ jobs:
         with:
           token: ${{ secrets.CODECOV_TOKEN }}
           files: test-report.xml
+          fail_ci_if_error: false
 
       - name: Check dependencies
         run: npm run checkDependencies