chore: import upstream snapshot with attribution

tests/test_execution_status_contract.py

@@ -0,0 +1,95 @@
+from __future__ import annotations
+
+import importlib
+
+
+def _execution_status_module():
+    return importlib.import_module("opensquilla.execution_status")
+
+
+def test_execution_status_defaults_to_unknown_normal_status() -> None:
+    module = _execution_status_module()
+
+    status = module.normalize_execution_status(None)
+
+    assert status == {
+        "version": 1,
+        "status": "unknown",
+        "exit_code": None,
+        "timed_out": False,
+        "truncated": False,
+        "reason": None,
+        "source": "unknown",
+        "preservation_class": "normal",
+    }
+
+
+def test_execution_status_rejects_invalid_status_with_fallback_reason() -> None:
+    module = _execution_status_module()
+
+    status = module.normalize_execution_status(
+        {
+            "version": 1,
+            "status": "not-a-status",
+            "source": "adapter",
+            "preservation_class": "normal",
+        }
+    )
+
+    assert status["status"] == "unknown"
+    assert status["reason"] == "invalid_status"
+
+
+def test_derive_is_error_is_true_only_for_terminal_failures() -> None:
+    module = _execution_status_module()
+
+    assert module.derive_is_error({"status": "success"}) is False
+    assert module.derive_is_error({"status": "unknown"}) is False
+    assert module.derive_is_error({"status": "error"}) is True
+    assert module.derive_is_error({"status": "timeout"}) is True
+    assert module.derive_is_error({"status": "cancelled"}) is True
+
+
+def test_execution_status_truncated_does_not_change_success_status() -> None:
+    module = _execution_status_module()
+
+    status = module.normalize_execution_status(
+        {
+            "version": 1,
+            "status": "success",
+            "exit_code": 0,
+            "timed_out": False,
+            "truncated": True,
+            "reason": None,
+            "source": "adapter",
+            "preservation_class": "retain_summary",
+        }
+    )
+
+    assert status["status"] == "success"
+    assert status["truncated"] is True
+    assert module.derive_is_error(status) is False
+
+
+def test_legacy_error_normalizes_to_diagnostic_execution_status() -> None:
+    module = _execution_status_module()
+
+    status = module.normalize_legacy_execution_status(is_error=True)
+
+    assert status["version"] == 1
+    assert status["status"] == "error"
+    assert status["source"] == "legacy"
+    assert status["reason"] == "legacy_missing_status"
+    assert status["preservation_class"] == "diagnostic"
+
+
+def test_legacy_non_error_normalizes_to_unknown_normal_status() -> None:
+    module = _execution_status_module()
+
+    status = module.normalize_legacy_execution_status(is_error=False)
+
+    assert status["version"] == 1
+    assert status["status"] == "unknown"
+    assert status["source"] == "legacy"
+    assert status["reason"] == "legacy_missing_status"
+    assert status["preservation_class"] == "normal"