When both OPENROUTER_API_KEY and OPENAI_API_KEY are set (e.g. OPENAI_API_KEY
in .bashrc), the wrong key was sent to OpenRouter causing auth failures.
Fixed key resolution order in cli.py and runtime_provider.py.
Fixes#289
Updated the authentication mechanism to store Codex OAuth tokens in the Hermes auth store located at ~/.hermes/auth.json instead of the previous ~/.codex/auth.json. This change includes refactoring related functions for reading and saving tokens, ensuring better management of authentication states and preventing conflicts between different applications. Adjusted tests to reflect the new storage structure and improved error handling for missing or malformed tokens.
