Fix build errors

[jeongyoonlee]

Proposed changes

This PR fixes the build errors generated after #831, which removed the runtime dependency of Cython (e.g., here), by using pip install -e . instead of python setup.py build_ext --inplace in the GitHub Action files. The installation document has been updated accordingly.

Types of changes

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• Bugfix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation Update (if none of the other choices apply)

Checklist

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• I have read the CONTRIBUTING doc
• I have signed the CLA
• Lint and unit tests pass locally with my changes
• I have added tests that prove my fix is effective or that my feature works
• I have added necessary documentation (if appropriate)
• Any dependent changes have been merged and published in downstream modules

Further comments

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[Copilot]

Pull Request Overview

This PR cleans up the build setup by removing deprecated fetch_build_eggs() calls and updating how NumPy include paths are acquired, then bumps the package version.

• Removed fetch_build_eggs() fallbacks for Cython and NumPy in setup.py
• Switched from np_get_include() to np.get_include() with an import numpy as np
• Updated version in pyproject.toml to 0.15.5dev

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
setup.py	Dropped fetch_build_eggs logic, imported NumPy, updated include
pyproject.toml	Bumped version from 0.15.4 to 0.15.5dev

Comments suppressed due to low confidence (3)

pyproject.toml:1

• Add a [build-system] section in pyproject.toml (e.g., requires = ["setuptools>=61", "wheel", "cython<=0.29.34", "numpy"], build-backend = "setuptools.build_meta") so that Cython and NumPy are installed before building extensions.

[project]

pyproject.toml:3

• [nitpick] The version string 0.15.5dev may not follow PEP 440 strict conventions; consider using 0.15.5.dev0 for a proper development release marker.

version = "0.15.5dev"

setup.py:47

• [nitpick] The top-level include_dirs in setup() may be redundant since each Extension already specifies include_dirs; you can remove it to reduce duplication.

include_dirs=[np.get_include()],

[Copilot]

Pull Request Overview

A PR that fixes build errors by updating installation commands in GitHub Action files and the package setup.

• Updates dependency fetching in setup.py to simplify use of Cython and numpy.
• Revises installation commands in docs and CI workflows to use pip install -e . and support newer Python versions.

Reviewed Changes

Copilot reviewed 7 out of 7 changed files in this pull request and generated 1 comment.

File	Description
setup.py	Adjusts dependency fetching and installation settings for Cython and numpy.
pyproject.toml	Updates package version to reflect development progress.
docs/installation.rst	Revises installation instructions, removing deprecated build commands.
.github/workflows/*	Updates Python version matrices and switches to pip install -e . for consistency.