fix: resolve ZoneInfo error by using IANA-compliant local timezone

[sleeper]

Replaced local timezone detection using tzinfo string (e.g. "CEST") with tzlocal.get_localzone_name() to ensure a valid IANA time zone (e.g. "Europe/Paris") is passed to ZoneInfo. This avoids runtime errors on macOS and other systems that return non-IANA tz abbreviations.

Description

Server Details

• Server: time
• Changes to: code

Motivation and Context

The mcp_time_server was not able to determine the local timezone on MacOS.

How Has This Been Tested?

I was able to run the server on MacOS.

Breaking Changes

No.

Types of changes

• [x] 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

• [x] I have read the MCP Protocol Documentation
• [x] My changes follows MCP security best practices
• [x] I have updated the server's README accordingly
• [x] I have tested this with an LLM client
• [x] My code follows the repository's style guidelines
• [x] New and existing tests pass locally
• [x] I have added appropriate error handling
• [x] I have documented all environment variables and configuration options

Additional context

[sleeper]

This should fix #1629 and #786

[Vonfry]

I meet the same issue on linux. And this fix looks good to me. Could any committers merge this?

[sleeper]

Thanks for merging!