[BUG] LM configurations lost when reloading a saved CoSTORM runner

[JamesHWade]

Description

When saving a CoStormRunner session and attempting to reload it later, the language model configurations are not properly preserved. The session loads with default LM configurations instead of the ones that were used in the original session. This causes inconsistency in behavior between original and reloaded sessions.

Additionally, sensitive authentication information was potentially being serialized with the LM configurations, creating a security risk.

Steps to Reproduce

1. Create a CoStormRunner instance with custom LM configurations
2. Run a partial session (e.g., through warm start or a few rounds of conversation)
3. Save the session using to_dict()
4. Try to reload the session using from_dict()
5. Observe that LM configurations are reset to default values

Expected Behavior

When reloading a saved session, all LM configurations should be preserved exactly as they were in the original session, while properly handling sensitive authentication data.

Environment

• OS: Ubuntu 22.04
• Python version: 3.10