docs: make retro review test plan concrete and windows-runtime aware

[paddymul]

Motivation

• Make the previous retroactive PR review actionable by converting high-level findings into exact test designs and acceptance criteria.
• Ensure the likely /load no_browser coercion bug and the pandas get_mode() pandas-3.0 compatibility concern have concrete reproducers and test vectors.
• Provide a Windows-aware CI strategy that preserves PR latency while improving platform signal via targeted smoke tests and a nightly expanded run.

Description

• Add and/or update the planning document docs/retroactive-pr-review-2026-02.md with a detailed /load no_browser test matrix, explicit pytest.mark.parametrize guidance, and recommended assertions and handler monkeypatching.
• Add concrete pandas get_mode() regression test cases to be added (numeric, non-numeric, NaN, empty, dtype edge cases) with file-target suggestions for unit tests.
• Propose a Windows hardening plan that introduces a @pytest.mark.windows_smoke marker, a PR-level smoke subset to run quickly, and a scheduled/nightly blocking Windows job for broader coverage, plus guidance to expand extras smoke tests from import checks to behavior checks.

Testing

• This is a documentation-only change so no unit or integration tests were added, and validation was performed by inspecting the updated file with sed -n '1,240p' docs/retroactive-pr-review-2026-02.md.
• The updated document was also reviewed with nl -ba docs/retroactive-pr-review-2026-02.md | sed -n '1,280p' to verify content and line layout.
• Repository state was checked with git status --short to confirm the file was staged for inclusion; these verification commands completed successfully.

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Codex Task

[github-actions]

📦 TestPyPI package published

pip install --index-strategy unsafe-best-match --index-url https://test.pypi.org/simple/ --extra-index-url https://pypi.org/simple/ buckaroo==0.12.9.dev22351743126

or with uv:

uv pip install --index-strategy unsafe-best-match --index-url https://test.pypi.org/simple/ --extra-index-url https://pypi.org/simple/ buckaroo==0.12.9.dev22351743126

MCP server for Claude Code

claude mcp add buckaroo-table -- uvx --from "buckaroo[mcp]==0.12.9.dev22351743126" --index-strategy unsafe-best-match --index-url https://test.pypi.org/simple/ --extra-index-url https://pypi.org/simple/ buckaroo-table