Add governed reusable workflow definitions

README.md

@@ -25,6 +25,18 @@ Instance state, resumable transitions, human activities, retries, and event
 subscriptions must build on the pinned definition and versioned module
 capabilities rather than bypassing them.
 
+Definitions can be complete flows or non-runnable templates at system,
+tenant, group, or user scope. Policy resolves whether a definition can be
+viewed, edited, started, reused, derived, or automated and returns the ordered
+source path shown in the editor. Derivation copies an immutable graph revision
+and records its hash, node-library version, source scope, actor, Policy
+decision, and effective ancestor limits.
+
+The start-node library distinguishes explicit user, API, scheduled, event, and
+parent-workflow starts. These are definition contracts only until the
+resumable Workflow instance runtime is implemented; the UI reports that
+limitation rather than presenting automation as operational.
+
 See [docs/CONCEPT.md](docs/CONCEPT.md) for the complete module concept.
 
 There is a BPMN component playing a major role here. Maybe this needs to