Add Rotating Calipers algorithm for convex polygon diameter

[Clear20-22]

Describe your change

• Add an algorithm?
• Fix a bug or typo in an existing algorithm?
• Add or change doctests? -- Note: Please avoid changing both code and tests in a single pull request.
• Documentation change?

This PR implements the Rotating Calipers algorithm in geometry/rotating_calipers.py. It computes the maximum Euclidean distance (polygon diameter) and the antipodal point pair of a set of 2D points in O(N log N) overall time (O(N) for the calipers sweep after monotone chain convex hull construction).

Checklist

• I have read CONTRIBUTING.md.
• This pull request is all my own work -- I have not plagiarized.
• I know that pull requests will not be merged if they fail the automated tests.
• This PR only changes one algorithm file. To ease review, please open separate PRs for separate algorithms.
• All new Python files are placed inside an existing directory.
• All filenames are in all lowercase characters with no spaces or dashes.
• All functions and variable names follow Python naming conventions.
• All function parameters and return values are annotated with Python type hints.
• All functions have doctests that pass the automated testing.
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[algorithms-keeper]

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🔗 Relevant Links

Repository:

• Contributing guidelines
• Project Euler solution guidelines

Python:

• Formatted string literals (f-strings)
• Type hints
• doctest
• unittest
• pytest

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[algorithms-keeper]

Variable and function names should follow the snake_case naming convention. Please update the following name accordingly: Point

[Copilot]

🟢 Approval recommended

The remaining test-coverage feedback is a non-blocking nit.

Pull request overview

Adds a rotating-calipers algorithm for computing the diameter and antipodal pair of 2D point sets.

Changes:

• Builds a monotone-chain convex hull.
• Computes diameter using rotating calipers.
• Handles degenerate inputs and includes doctests.

File summaries

File	Summary	Review finding
geometry/rotating_calipers.py	Implements hull construction, geometry helpers, and diameter calculation.	Nit (1 vote): add an asymmetric convex-polygon doctest to strengthen sweep validation.

Review details

Suppressed comments (1)

geometry/rotating_calipers.py:162

• The end-to-end doctests exercise the sweep only on an axis-aligned rectangle (plus degenerate 1D cases). Because that input has strong symmetry and repeated antipodal-area ties, it can pass even if pointer advancement or antipodal selection is wrong for a general convex polygon. Add an asymmetric convex polygon, ideally with interior and/or unsorted points, and assert its known brute-force diameter and returned endpoints.

    >>> rotating_calipers([Point(1.0, 1.0)])
    Traceback (most recent call last):
        ...
    ValueError: At least 2 points are required to compute polygon diameter.
    """

• Files reviewed: 1/1 changed files
• Comments generated: 0
• Review effort level: Lite

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