1) Get the Google Slides presentation ID from the URL
(the portion between /d/ and
/edit).
2) Add it to data/agendas.json under the
correct ISO week key (e.g. 2025-W36).
3) Ensure the presentation is shared as "Anyone with the
link can view" for embedding to work.
4) Page auto-selects the current ISO week if present,
else the most recent prior.
5) Share direct links using the Copy Link button (hash
stores class & week).
Local development: Run a local server
(python -m http.server 8000) since
file:// URLs cannot fetch JSON.