fix(consistency): skip terminal orphan DB tasks in C-12 check

Cancelled or done DB tasks without file backing are historical duplicates
after workplan linkage. Do not warn on active workstreams when the orphan
is already terminal.

scripts/consistency_check.py

@@ -1264,10 +1264,10 @@ def check_repo(api_base: str, repo_slug: str, repo_path_override: str | None = N
                 if db_t["id"] not in file_task_sh_ids:
                     db_t_status = normalise_task_status(db_t.get("status", "todo"))
                     open_task = db_t_status not in TERMINAL_TASK_STATUSES
-                    # Closed workstreams can legitimately retain terminal historical
-                    # DB tasks from earlier duplicates. The public task DELETE route
+                    # Terminal orphans (cancel/done) are historical duplicates after
+                    # file linkage or explicit retirement. The public task DELETE route
                     # is a cancel operation, so these are not further actionable.
-                    if ws_finished and not open_task:
+                    if not open_task:
                         continue
                     # Auto-cancel fixable when workstream is finished and task is open.
                     fixable = ws_finished and open_task