Remove the fully commented-out PythonWorkflowWorkerSpec

### Task Summary

`PythonWorkflowWorkerSpec.scala` contributes zero test suites — every line in it is commented out, including the `package` declaration, so it compiles to a licence header.

| File | Lines | Live lines |
| --- | ---: | ---: |
| `amber/.../engine/architecture/pythonworker/PythonWorkflowWorkerSpec.scala` | 201 | 0 |

The commented body targets APIs deleted long ago (`InitializeOperatorLogicHandler`, `UpdateInputLinkingHandler`, `OpenOperator`, `engine.common.Constants`, the old `PhysicalLink` shape), so it cannot be un-commented as-is. Live `PythonWorkflowWorker` coverage lives in the `@IntegrationTest` e2e specs, which this file does not participate in.

Pure deletion, no behaviour change: −201 lines.

### Task Type

- [x] Refactor / Cleanup

Open amber/.../engine/architecture/pythonworker/PythonWorkflowWorkerSpec.scala and confirm that all 201 lines are commented out and reference deleted APIs. Remove the file, then run the relevant test or build checks and verify that live PythonWorkflowWorker coverage remains in the @IntegrationTest end-to-end specs.

Written by the indexing model from the issue text.