Fix week 1 in december

[tomkooij]

I use klascal for looking up my Zermelo schedule. THANKS!
(In my own fork, I'm working on things useful for teachers, such as showing the schedule of other teachers) never mind that.

Today I noticed klascal was showing the schedule of january 2025. This is because we rolled over to week 01 of 2026, but it is still 2025.

// Dec, 29th
new Date().getMonth();  // 11
new Date().getDate(); // 29
new Date().getFullYear(); // 2025

// week 1 of 2026, but year is still 2025
new Date().getFullYear(); // 2025
new Date().getWeek(); // 1 

This is a quick fix.

[vercel]

@tomkooij is attempting to deploy a commit to the klascal's projects Team on Vercel.

A member of the Team first needs to authorize it.

[tomkooij]

Never mind the force-push: I accidentally pushed a branch with my previous work. I rebased this on upstream/main and forced push.
EDIT1: I did not notice 3a9ef2a .
EDIT2: merged it in. Bug was still present. Seems fixed on this branch.