Bump python to 3.10, support 3.13 and higher

[cptartur]

Closes #

Introduced changes

• This PR contains breaking changes

[Copilot]

Pull Request Overview

This PR upgrades the minimum supported Python version from 3.9 to 3.10 and removes the upper bound restriction to support Python 3.13 and higher.

Key changes:

• Minimum Python version increased from 3.9 to 3.10
• Maximum Python version constraint changed from <3.13 to <4 (effectively supporting 3.13+)
• Test matrix and CI workflows updated to test with Python 3.10 and 3.14

Reviewed Changes

Copilot reviewed 9 out of 10 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
pyproject.toml	Updated Python version requirement from ">=3.9, <3.13" to ">=3.10, <4"
poetry.lock	Removed Python 3.9-specific dependencies (importlib-metadata, zipp), added Python 3.13+ compatibility packages (standard-imghdr), and updated dependency markers
pylint_todo_checker.py	Added raw string prefix to regex pattern
docs/migration_guide.rst	Added migration guide entry documenting the Python version change
.readthedocs.yml	Updated Python version from 3.9 to 3.10
.python-version	Updated from 3.9.12 to 3.10
.pylintrc	Updated py-version from 3.9 to 3.10
.github/workflows/package.yml	Updated CI Python version from 3.9 to 3.10
.github/workflows/checks.yml	Updated CI test matrix from ["3.9", "3.12"] to ["3.10", "3.14"] and updated all Python version references
.github/ISSUE_TEMPLATE/bug_report.yaml	Updated bug report template to reference Python 3.10 as minimum version

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[Arcticae]

Clue for fixing this:
python-pillow/Pillow#5042
(the issue seems to be building from source)