feat(JVNAUTOSCI-1446): make workflow creation VWL-native

[witbrock]

Summary

• add first-class workflow action-contract concepts and contract-aware action resolution
• add authored workflow publication lifecycle semantics so drafts stay loadable but undiscoverable until publish
• migrate workflow-creation authoring to concept-backed workflow_authoring actions and canonical graph predicates
• update tests and the VWL manual, and materialise the workflow-creation graph/action contracts in Vontology

Validation

• pdm run pyright src/backend/workflows/action_registry.py src/backend/workflows/durable/workflow_creation_workflow.py src/backend/workflows/engine.py src/backend/workflows/vontology_loader.py src/backend/workflows/workflow_concept_authority_service.py src/backend/workflows/workflow_action_contracts.py src/backend/workflows/workflow_creation_contracts.py src/backend/services/workflow_discovery_service.py tests/backend/test_workflow_creation_workflow.py tests/backend/test_vontology_loader.py tests/backend/test_workflow_discovery_service.py
• pdm run pytest tests/backend/test_vontology_loader.py tests/backend/test_workflow_concept_authority_service.py tests/backend/test_workflow_creation_workflow.py tests/backend/test_workflow_discovery_service.py -q
• pdm run pytest tests -m lane_backend_workflows -q

Vontology materialisation

• republished #V#von_workflow_creation_workflow into von_db
• ensured all workflow_authoring action-contract concepts exist
• updated the workflow capability-gap note on #V#von_workflow_creation_workflow