v0.13.1 release planning

[kandersolar]

We're a little past the quarterly release date (which, of course, is more of a suggestion than a real schedule). Anyway let's try to cut the release next week.

These PRs seem like they could be merged with a little work:

• Add 2025 coefficients for Huld model #2486
• Adds k parameter to temperature.ross #2521
• [BUGFIX] Inconsistent naming of [cross_]axis_tilt / [cross_]axis_slope #2543
• Drop Python 3.9 #2547
• use inferred window length in detect clearsky check #2550
• irradiance.py updates: glossary term links and units  #2311
• Fix failing Meteonorm tests #2548
• publish.yml: use trusted publishing instead of API token #2549
• fix this test warning: https://github.com/pvlib/pvlib-python/actions/runs/17922536039/job/50960845195#step:9:80

Anything else?

[RDaxini]

Tentative #2311

[wholmgren]

Thanks for tracking the release schedule @kandersolar. I added #2550 to the milestone

[RDaxini]

[ ] fix this test warning: https://github.com/pvlib/pvlib-python/actions/runs/17922536039/job/50960845195#step:9:80

#2551