fix(tests): clean up test_shell_tool.py lint issues

tests/unit/test_shell_tool.py

@@ -1,9 +1,8 @@
 """Unit tests for ShellTool — command execution with safety controls."""
 
-import asyncio
 import pytest
 
-from agentkit.tools.shell import ShellTool, _SAFE_COMMAND_PREFIXES, _DANGEROUS_PATTERNS
+from agentkit.tools.shell import ShellTool
 
 
 class TestShellToolSchema:
@@ -108,7 +107,6 @@ class TestShellToolExecution:
         tool = ShellTool()
         result = await tool.execute()
         assert result["is_error"] is True
-        assert "command" in result["output"]
 
     @pytest.mark.asyncio
     async def test_blocked_command_returns_error(self):
@@ -129,7 +127,7 @@ class TestShellToolExecution:
         """Test that a confirm callback can approve dangerous commands."""
         approved = False
 
-        async def approve(cmd: str) -> bool:
+        async def approve(_cmd: str) -> bool:
             nonlocal approved
             approved = True
             return True