C-39: accept task-block blocked_on: message-from:<agent> as an owner-return wait (rule 6)

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

Assistant: claude-code
Assistant-Model: sonnet
Assistant-Process: 237582@bnt-lap001
Assistant-Session: f2b3d9f1-8fb9-4b9c-bc2b-837ec5dfc826

scripts/consistency_check.py

@@ -2017,7 +2017,12 @@ def check_repo(
             task_dep_targets = _frontmatter_depends_on_workplans(task) + _frontmatter_depends_on_tasks(task)
             wait_fields = _task_wait_fields(task)
             if t_status == "wait" and normalised_file_status not in CLOSED_WORKSTREAM_STATUSES:
-                if not task_dep_targets and not wait_fields["needs_human"]:
+                # Rule 6: an owner-return wait with no workplan id yet is
+                # qualified by the C-25 vocabulary on the task block.
+                owner_return = bool(
+                    _BLOCKED_ON_RE.match(str(task.get("blocked_on") or "").strip())
+                )
+                if not task_dep_targets and not wait_fields["needs_human"] and not owner_return:
                     report.add(
                         severity="WARN", check_id="C-39",
                         message=(