feat: persist and edit versioned workflow definitions

README.md

@@ -11,13 +11,19 @@ between modules without importing their implementations. It coordinates cases,
 tasks, forms, files, templates, mail, appointments, payments, and records
 through capabilities, events, commands, and DTOs.
 
-The first executable slice exposes a workflow-specific node library and graph
-validation API through `/workflow/node-types` and
-`/workflow/definitions/validate`. It uses Core's domain-neutral definition graph
-contract, but applies Workflow constraints: exactly one trigger, at least one
-outcome, governed configuration fields, connected nodes, and permitted loops for
-correction and retry paths. Dataflow uses the same graph contract with its own
-acyclic transformation library.
+Workflow exposes a workflow-specific node library, a full definition editor,
+validation APIs, tenant-isolated definitions, and immutable graph revisions.
+Activation pins the exact revision that future instances will execute. It uses
+Core's domain-neutral definition graph contract, but applies Workflow
+constraints: exactly one trigger, at least one outcome, governed configuration
+fields, connected nodes, and permitted loops for correction and retry paths.
+Dataflow uses the same graph contract with its own acyclic transformation
+library.
+
+The current slice deliberately stops before executing process instances.
+Instance state, resumable transitions, human activities, retries, and event
+subscriptions must build on the pinned definition and versioned module
+capabilities rather than bypassing them.
 
 See [docs/CONCEPT.md](docs/CONCEPT.md) for the complete module concept.