fix: map zero magnitude to black in max_chroma_colormap

[kilo-code-bot]

Addresses the CodeRabbit comment about the zero-input contract in max_chroma_colormap.

Issue: Both colormaps' docstrings state that magnitude 0 maps to black, and const_chroma_colormap honors it, but max_chroma_colormap returned a near-black (0.051, 0, 0.001) because the C lookup-table interpolation leaves a tiny residual chroma at J=0.

Fix: Explicitly set zero-valued input to black, consistent with the documented contract and const_chroma_colormap. Updated the docstring example accordingly.

The zero-input behavior is a library concern, separate from the CI migration in #22.

Summary by CodeRabbit

• Bug Fixes
  • Zero-valued inputs now render explicitly as black.
  • Updated the maximum-chroma colormap example output for zero-magnitude values.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro Plus

Run ID: 02aff8f7-72a4-4b01-932a-4697093594c3

📥 Commits

Reviewing files that changed from the base of the PR and between 410aad7 and 27f5236.

📒 Files selected for processing (1)

• complex_colormap/cplot.py

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📝 Walkthrough

Walkthrough

The colormap now maps exactly zero-valued inputs to black after RGB conversion. The documented zero-magnitude example matches the new output.

Changes

Zero-value colormap output

Layer / File(s)	Summary
Zero-value black override complex_colormap/cplot.py	The RGB conversion maps exactly zero-valued inputs to black. The example output now documents black for zero magnitude.

Estimated code review effort: 1 (Trivial) | ~5 minutes

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title clearly describes the main change: mapping zero-magnitude values to black in max_chroma_colormap.
Docstring Coverage	✅ Passed	Docstring coverage is 100.00% which is sufficient. The required threshold is 80.00%.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

✨ Finishing Touches 💡 1

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📝 Generate docstrings

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🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch fix/max-chroma-zero-black

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