style: add annotations and return types to test

Author: Hundao

core/tests/test_tool_context_propagation.py

@@ -9,6 +9,8 @@
 Fix: wrap the executor call in contextvars.copy_context().run().
 """
 
+from __future__ import annotations
+
 import pytest
 
 from framework.graph.event_loop.tool_result_handler import execute_tool
@@ -19,14 +21,14 @@
 class _ToolCallEvent:
     """Minimal stand-in for ToolCallEvent used by execute_tool."""
 
-    def __init__(self, tool_name: str, tool_input: dict):
+    def __init__(self, tool_name: str, tool_input: dict) -> None:
         self.tool_use_id = "test_id"
         self.tool_name = tool_name
         self.tool_input = tool_input
 
 
 @pytest.mark.asyncio
-async def test_execution_context_propagates_to_tool_executor():
+async def test_execution_context_propagates_to_tool_executor() -> None:
     """data_dir set via set_execution_context must be visible inside
     the tool executor even though it runs in a thread pool."""
 
@@ -62,7 +64,7 @@ def capturing_executor(tool_use: ToolUse) -> ToolResult:
 
 
 @pytest.mark.asyncio
-async def test_execution_context_none_when_not_set():
+async def test_execution_context_none_when_not_set() -> None:
     """When no execution context is set, executor should still work
     (context is None, not an error)."""