Classify invocable deadline overruns consistently

Classify asyncio timeout overruns from invocable activity handlers as deadline exceeded failures.

Author: durable-workflow-ops

src/durable_workflow/invocable.py

@@ -103,7 +103,7 @@ async def handle(self, envelope: Mapping[str, Any]) -> dict[str, Any]:
                 stack_trace=traceback.format_exc(),
                 retryable=False,
             )
-        except TimeoutError as exc:
+        except (asyncio.TimeoutError, TimeoutError) as exc:
             return self._failure(
                 task_input,
                 started,

tests/test_invocable.py

@@ -17,7 +17,8 @@
 
 
 def load_fixture(name: str) -> dict[str, Any]:
-    return json.loads((FIXTURES / name).read_text())
+    loaded: dict[str, Any] = json.loads((FIXTURES / name).read_text())
+    return loaded
 
 
 def _iso(timestamp: datetime) -> str:
@@ -118,6 +119,8 @@ async def slow_charge() -> dict[str, bool]:
     assert result.failed is True
     assert result.retryable is True
     assert result.deadline_exceeded is True
+    assert result.failure is not None
+    assert result.failure.timeout_type == "deadline_exceeded"
     assert result.result is None