fix(review): restore error-free assertion in test_get_recipe_uses_project_dir

The assertion 'assert "\"error\"" not in result' was removed in 05bda5b
without replacement. The new test_recipe_resource_returns_error_for_invalid_recipe
covers the error path via mock but not the happy-path real-recipe assertion.
Restore the error-free check to prevent regressions where get_recipe returns
both the recipe name and an error key simultaneously.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: Trecek

tests/server/test_tools_kitchen_gate_features.py

@@ -373,6 +373,9 @@ def test_get_recipe_uses_project_dir(tmp_path, monkeypatch):
 
         result = get_recipe("test-get-recipe-project-dir")
 
+    assert '"error"' not in result, (
+        f"get_recipe failed to find recipe in project_dir={different_dir}. Result: {result}"
+    )
     assert "test-get-recipe-project-dir" in result, (
         f"get_recipe did not use project_dir for recipe lookup. Result: {result}"
     )