Variable DEFAULT_SERVER_CONFIGConst

Default MJServer configuration values. These provide sensible defaults for all optional settings, with environment variable overrides.

Priority order (highest to lowest):

1. User's mj.config.cjs overrides
2. Environment variables (referenced here in defaults)
3. Hardcoded default values

This means minimal configs only need to override if they want something different than both the environment variable AND the default value.