The test_init_defaults test expected OperativeAgent class defaults
(temperature=0.3) but didn't mock load_config(), so when config loaded
successfully it returned the global default (0.7) instead.
Fix: mock load_config to raise, so the test properly validates the
class-level _default_temperature/max_tokens/max_turns fallback path.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>