Add the WorkflowVersion domain resource with exactly entrypoint, files,
and workflow_dependencies, plus strict WorkflowPath validation and
deterministic canonical raw JSON. Semantic validation of graph imports,
templates, file references, workflow.toml rules, Dockerfile paths, and
exact child-workflow dependency bindings lives in the new
fabro-workflow-version crate, which validates the complete stored
dependency closure through the shared blob store before writing a root.
The authenticated create-only POST /api/v1/workflow-versions endpoint
ships with its OpenAPI contract, Rust type replacements, and generated
TypeScript client.
Squashed from the resource commits of the original combined branch;
the walker unification this builds on landed separately.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
