Fix News schema validation for searchNews

[zorkary]

Summary

• Normalize the live OpenAPI News schema before FastMCP tool generation.
• Remove rest_id from the required fields for News when present.
• Add id as an accepted News property when the schema only exposes rest_id.
• Add a small unit test for the News schema normalization behavior.

Why

searchNews can fail output validation because the hosted OpenAPI spec declares News.required = ["rest_id"], while news.fields exposes id and live /2/news/search responses include id without rest_id.

This keeps XMCP usable while the hosted OpenAPI schema and live News response shape differ.

Validation

• Ran git diff --check.
• Ran python -m unittest test_server.py.
• Parsed server.py with ast.parse.
• Exercised normalize_known_spec_mismatches on a minimal News schema.
• Loaded the hosted OpenAPI spec and verified the filtered News schema has no required rest_id and includes id.

[CLAassistant]

All committers have signed the CLA.

[zorkary]

Opened issue #16 to describe the hosted OpenAPI/live API mismatch separately from this draft patch. I am leaving this PR as draft unless maintainers prefer the XMCP-side compatibility normalization here.