# Map unspecified sink endpoint phase to creating

## Analysis

| Area | Current behavior | Intended behavior |
| --- | --- | --- |
| dataflow-service-ng sink endpoint worker | `PHASE_UNSPECIFIED` falls through to an empty entity status because it is combined with `CREATING` using bitwise OR | `PHASE_UNSPECIFIED` is treated as `creating` while the regional endpoint is still being created |
| Console sink endpoint API | An empty entity status serializes as `SINK_ENDPOINT_STATUS_UNSPECIFIED` | Return `SINK_ENDPOINT_STATUS_CREATING` for the affected endpoint |

The change is limited to the regional-to-entity phase mapping. No schema or protobuf change is required.

## Execution steps

1. Update `endpointStatusRegional2Entity` so `CREATING` and `PHASE_UNSPECIFIED` are separate cases, both returning the creating entity status.
2. Add a table-driven unit test covering both phases and the existing terminal/intermediate mappings.
3. Run `gofmt` and the sink endpoint model tests with `go test ./app/models/sink_endpoint/impl` from `dataflow-service/dataflow-service-ng`.
4. Run the module-local verification command required by the repository, or report any environment limitation.

## Risk assessment

This preserves all existing explicit phase mappings. The only behavior change is that an empty regional phase no longer overwrites a creating endpoint with an empty status; it is exposed as creating and remains retryable.