feat: Adjust log levels for trace logging

[kyle-leonhard]

Reduce log levels on per-connection/request/message events to trace from info.

I considered using DEBUG which is the default level used by Axum for request logging. WDYT?

Motivation and Context

Emitting per-connection and message logs at INFO level is unexpected, in my experience. Using a finer level allows filtering to be effective without requiring users to set module level configuration.

How Has This Been Tested?

Locally with my MCP server

Breaking Changes

None

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Documentation update

Checklist

• I have read the MCP Documentation
• My code follows the repository's style guidelines
• New and existing tests pass locally
• I have added appropriate error handling
• I have added or updated documentation as needed

Additional context

None

[jokemanfire]

I'm not sure if the level of these logs needs to be lowered. What's your opinion? @4t145

[4t145]

Sorry for late response

Using a finer level allows filtering to be effective without requiring users to set module level configuration.

Current log level are base on the following standards

• session/connection level: info
• reqeust/message level: debug
• more verbose log: trace

I don't think set all level to trace could be "finer", there are more logs during the connect/request, if they are all in trace level, it would be inconvenient to distinguish them. I think the debug level could be OK. But after all, set module level configuration won't cost you a lot of time. So I am not going to close this pr and maybe more people can give me some suggestion.