[MEDIUM] test result parsing can attach unrelated nested messages to non-passing cases

[Daliys]

Problem

GetTestResults falls back to the first descendant <message> anywhere under a non-passing test case when no <failure><message> exists.

Evidence

• Editor/MCPServerMethods.TestResults.cs:36-42 skips only Passed/Skipped results.
• For other statuses, it uses testCase.Element("failure")?.Element("message")?.Value ?? testCase.Descendants("message").FirstOrDefault()?.Value.
• The fallback is not scoped to failure/error/reason nodes.

Impact

Inconclusive, Error, or other non-passing NUnit XML shapes can surface an unrelated nested message as the failure reason, misleading callers diagnosing test failures.

Suggested fix

Scope fallback message extraction to known result containers such as failure, reason, or output, and preserve the result status when no reason exists instead of grabbing any descendant message.

Source report

Imported from audit report item: Editor/MCPServerMethods.TestResults.cs:41.

[Daliys]

Fixed in #150.