test: cover stale ledger outbox lease updates

Co-authored-by: genichin <4282227+genichin@users.noreply.github.com>

tests/adapters/persistence/test_postgresql_ledger_outbox.py

@@ -169,6 +169,45 @@ def test_claim_expiry_allows_safe_recovery_after_worker_crash(pg_clean):
     assert [item.correlation_id for item in claimed_b] == [row.correlation_id]
 
 
+def test_stale_claim_cannot_overwrite_new_owner_outcome(pg_clean):
+    now = {"t": datetime(2026, 6, 4, tzinfo=UTC)}
+    outbox_a = PostgreSQLLedgerOutbox(
+        pg_clean,
+        instance_key="inst-a",
+        claim_ttl_sec=5.0,
+        worker_id="worker-a",
+        clock=lambda: now["t"],
+    )
+    outbox_b = PostgreSQLLedgerOutbox(
+        pg_clean,
+        instance_key="inst-a",
+        claim_ttl_sec=5.0,
+        worker_id="worker-b",
+        clock=lambda: now["t"],
+    )
+    row = outbox_a.enqueue(_trade(execution_id="pg-stale"))
+
+    [claim_a] = outbox_a.claim_pending()
+    now["t"] = datetime(2026, 6, 4, 0, 0, 6, tzinfo=UTC)
+    [claim_b] = outbox_b.claim_pending()
+    outbox_b.mark_outcome(
+        row.correlation_id,
+        OutboxOutcome.COMPLETED,
+        expected_claim_expires_at=claim_b.claim_expires_at,
+    )
+
+    stored = outbox_a.mark_outcome(
+        row.correlation_id,
+        OutboxOutcome.RETRYABLE_FAILURE,
+        error="stale owner",
+        next_retry_at=now["t"],
+        expected_claim_expires_at=claim_a.claim_expires_at,
+    )
+
+    assert stored.status is WorkItemStatus.COMPLETED
+    assert stored.last_outcome is OutboxOutcome.COMPLETED
+
+
 def test_writer_records_retryable_403_without_cross_instance_delivery(pg_clean):
     class _ForbiddenLedger:
         def __init__(self):