fix(core): emit LF newlines for tsv output

[rohan-patnaik]

Fixes #33385

Summary

This forces tsv output streams to use LF newlines before writing the formatted result.

Why

On Windows, Python text-mode output can translate \n into \r\n. That makes az ... -o tsv unsafe in bash-style command substitution because intermediate values keep a trailing \r, which can then break follow-up CLI calls.

Test plan

• .venv/bin/python -m pytest src/azure-cli-core/azure/cli/core/tests/test_output.py
• .venv/bin/python -m compileall -q src/azure-cli-core/azure/cli/core/_output.py src/azure-cli-core/azure/cli/core/tests/test_output.py
• git diff --check

[azure-client-tools-bot-prd]

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[azure-client-tools-bot-prd]

Hi @rohan-patnaik,
Since the current milestone time is less than 7 days, this pr will be reviewed in the next milestone.

[azure-client-tools-bot-prd]

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[microsoft-github-policy-service]

Thank you for your contribution @rohan-patnaik! We will review the pull request and get back to you soon.

[Copilot]

Pull request overview

Note

Copilot was unable to run its full agentic suite in this review.

Adds a TSV-specific behavior to force LF (\n) newlines during output, and introduces a regression test to ensure TSV output remains consistent across platforms (notably Windows).

Changes:

• Add a regression test validating TSV output uses LF newlines even when the stream is configured for CRLF.
• Override AzOutputProducer.out() to reconfigure the output stream newline handling when output format is tsv.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
src/azure-cli-core/azure/cli/core/tests/test_output.py	Adds regression test asserting TSV output is LF-terminated.
src/azure-cli-core/azure/cli/core/_output.py	Reconfigures output stream newline handling for TSV via out() override.

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[rohan-patnaik]

Addressed in d523bf1: out() now returns super().out(...) and passes the reconfigured stream through as out_file=file.

[yonzhan]

Thank you for your contribution! We will review the pull request and get back to you soon.

[github-actions]

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