chore: add_protocol (#47)

## Description

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In case there is no issue present for your PR, please consider creating one.
At least please give us some description what you are trying to achieve and why your change is needed. -->

relates to #1234

## Checklist

- [ ] Issue was linked above
- [ ] Code format was applied: `make fmt`
- [ ] Examples were added / adjusted (see `examples/` directory)
- [x] Docs are up-to-date: `make generate-docs` (will be checked by CI)
- [ ] Unit tests got implemented or updated
- [ ] Acceptance tests got implemented or updated (see e.g. [here](f5f99d1709/stackit/internal/services/dns/dns_acc_test.go))
- [x] Unit tests are passing: `make test` (will be checked by CI)
- [x] No linter issues: `make lint` (will be checked by CI)

Reviewed-on: #47
Reviewed-by: Andre_Harms <andre.harms@stackit.cloud>
Co-authored-by: Marcel S. Henselin <marcel.henselin@stackit.cloud>
Co-committed-by: Marcel S. Henselin <marcel.henselin@stackit.cloud>

.github/workflows/ci.yaml

@@ -146,6 +146,17 @@ jobs:
       - name: Test
         run: make test
 
+      - name: Check coverage threshold
+        shell: bash
+        run: |
+          make coverage
+          COVERAGE=$(go tool cover -func=coverage.out | grep total | awk '{print $3}' | sed 's/%//')
+          echo "Coverage: $COVERAGE%"
+          if (( $(echo "$COVERAGE < 80" | bc -l) )); then
+            echo "Coverage is below 80%"
+            # exit 1
+          fi
+
       - name: Archive code coverage results
         uses: actions/upload-artifact@v4
         with: