OPT_METROPOLISを４次項まで対応

[K-Suzuki-Jij]

変更

sample_huio関数において、updater=OPT_METROPOLISとすると、ある変数に対して最もエネルギーが下がるような最適遷移が行われます。
現在のmainの実装ではこの最適遷移が行われるのはz^2のような２乗項だけでしたが、これを４乗項まで行うように変更しました。

[Copilot]

Pull Request Overview

This PR extends the optimal Metropolis updater (OPT_METROPOLIS) in the sample_huio function to handle polynomial terms up to 4th degree, expanding from the previous limitation of only quadratic (2nd degree) terms.

• Extended optimal transition capability from quadratic to quartic polynomial terms
• Added new polynomial minimum finding utility functions for cubic and quartic cases
• Refactored the variable degree tracking system to use a more efficient vector-based approach

Reviewed Changes

Copilot reviewed 10 out of 10 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
include/openjij/utility/min_polynomial.hpp	New utility functions for finding minimum values of integer polynomials up to degree 4
include/openjij/system/integer_polynomial_sa_system.hpp	Extended GetMinEnergyDifference to handle cubic and quartic coefficients using new utility functions
include/openjij/graph/integer_polynomial_model.hpp	Replaced set-based degree tracking with vector-based approach for better performance
include/openjij/updater/single_integer_move.hpp	Updated method names to reflect extended capability from quadratic to quartic
include/openjij/system/integer_quadratic_sa_system.hpp	Updated method names for consistency
tests/cxxtest/utility/min_polynomial.hpp	Comprehensive test cases for the new polynomial minimum finding functions
tests/cxxtest/graph/integer_polynomial_model.hpp	Updated tests to use new degree tracking API
tests/cxxtest/utility/all.hpp	Added include for new polynomial utility tests
tests/cxxtest/cxxtest.cpp	Added include for new polynomial utility header
openjij/declare.hpp	Updated Python bindings to use new degree tracking API

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[j-i-k-o]

LGTM