fix(tests): preserves_body test \$Note stub needs project_id

The knowledge-note return path in create_note_tool reads note.project_id;
the SimpleNamespace fake didn't define it, so the tool crashed with
AttributeError instead of returning. The task-branch test already
included project_id; mirror that here.

tests/test_tools_notes.py

@@ -64,7 +64,11 @@ async def test_create_note_tool_preserves_body_for_knowledge_notes():
 
     async def fake_create_note(**kwargs):
         captured.update(kwargs)
-        return SimpleNamespace(id=1, title=kwargs["title"], status=None)
+        # Knowledge-note return path reads note.project_id; SimpleNamespace
+        # needs the attribute even when it's None.
+        return SimpleNamespace(
+            id=1, title=kwargs["title"], status=None, project_id=None,
+        )
 
     with patch(
         "fabledassistant.services.tools.notes.create_note", new=fake_create_note,