Fix JSON string parsing for UUID tool arguments

[linhongyu510]

Fixes #1873.

Motivation and Context

This fixes JSON string pre-parsing for non-string tool argument annotations such as UUID.

Previously, pre_parse_json() skipped all JSON values parsed into primitive types, including strings. This preserved string-like annotations correctly, but caused non-string annotations such as UUID to receive the original JSON-encoded string with surrounding quotes.

How Has This Been Tested?

env -u PYTHONHOME -u PYTHONPATH uv run pytest tests/server/mcpserver/test_func_metadata.py
env -u PYTHONHOME -u PYTHONPATH uv run ruff check src/mcp/server/mcpserver/utilities/func_metadata.py tests/server/mcpserver/test_func_metadata.py
env -u PYTHONHOME -u PYTHONPATH uv run pyright src/mcp/server/mcpserver/utilities/func_metadata.py tests/server/mcpserver/test_func_metadata.py

Breaking Changes

None.

Types of changes

• Bug fix (non-breaking change which fixes an issue)

Checklist

• I have disclosed AI assistance and can explain the change in my own words
• I have read the MCP Documentation
• My code follows the repository's style guidelines
• New and existing tests pass locally

[github-actions]

This PR has been closed automatically. This repo only keeps pull requests open when they come from a maintainer, or from a contributor a maintainer has assigned to the linked issue, and you aren't currently assigned to #1873.

If a maintainer assigns you to #1873, this PR reopens on its own and there's nothing more you need to do here. Assignment is a maintainer call based on capacity; comments that only ask to be assigned don't factor in. What does help is engaging on the issue itself by confirming the repro, explaining why it matters for your use case, or describing the approach you'd take.

You're welcome to keep pushing commits here (just avoid force-pushing, since GitHub can't reopen a rewritten branch), but that on its own won't get the PR reviewed or the issue assigned, and realistically most auto-closed PRs stay closed. There's no need to open a new PR either way.

CONTRIBUTING.md has the full reasoning, but in short:

• We're a small team with very little capacity to review community PRs right now.
• Many recent PRs are AI-generated with little human review, and reviewing one carefully still costs a maintainer as much time as it ever did. A well-described issue is usually more useful to us than the code.

Maintainers: reopen, remove missing-issue-link, or add bypass-issue-check to override.