Fix #1933: Using transport="stdio" closes real stdio, causing ValueError after se#2538
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sherlock-488 wants to merge 3 commits intomodelcontextprotocol:mainfrom
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…extprotocol#2366) Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com> Co-authored-by: Max Isbey <224885523+maxisbey@users.noreply.github.com>
…extprotocol#2366) Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com> Co-authored-by: Max Isbey <224885523+maxisbey@users.noreply.github.com>
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Fixes #1933
Stdio_server() wraps sys.stdin.buffer/sys.stdout.buffer directly, causing the real stdio file descriptors to be closed when the context manager exits, making subsequent I/O raise ValueError.
I also updated the relevant tests for this path.
Tests:
uv run --frozen pytest tests/server/test_stdio.py -vI used an AI assistant while preparing the patch, and manually reviewed the diff and test results before opening this PR.