Add support for Python 3.14

[NicolaCourtier]

Description

Extend support to Python 3.14.

Fixes #939

Type of change

Please add a line in the relevant section of CHANGELOG.md to document the change (include PR #).

Important checks:

Please confirm the following before marking the PR as ready for review:

• No style issues: $ pre-commit run or $ nox -s pre-commit (see CONTRIBUTING.md for how to set this up to run automatically when committing locally, in just two lines of code)
• All tests pass: nox -s tests
• The documentation builds: nox -s doctest
• Code is commented for hard-to-understand areas
• Tests added that prove fix is effective or that feature works

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 90.88%. Comparing base (4628a65) to head (c07647a).
⚠️ Report is 50 commits behind head on develop.

Additional details and impacted files

@@             Coverage Diff             @@
##           develop     #940      +/-   ##
===========================================
+ Coverage    89.41%   90.88%   +1.47%     
===========================================
  Files           63       73      +10     
  Lines         4857     5686     +829     
===========================================
+ Hits          4343     5168     +825     
- Misses         514      518       +4     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.

[agriyakhetarpal]

LGTM, thanks @NicolaCourtier!

Side note: I was looking through the trove classifiers we list, and we have "Development Status :: 3 - Alpha" (which I feel is a bit outdated, considering we've at least moved into a "Development Status :: 4 - Beta" at this point, given the JOSS paper), and we have "License :: OSI Approved :: BSD License", which is now deprecated and discouraged in favour of PEP 639 that offers better licensing metadata. Would you like me to update them in another PR?

[NicolaCourtier]

Oh, yes! Please do @agriyakhetarpal