This commit was generated using Copilot, with GPT-5-Codex (Preview),
using this prompt:
> Some of the labels don't fit in their boxes at lower zoom. Remove
> labels as soon as they don't fit in their boxes.
I made no changes to Copilot's suggestions.
This includes drawing custom and labeling custom lines with JOSM, which
this commit introduces, and adding a style function to display them
differently on the map. Per Eric's feedback, I also adjusted the weight
of the lines at different zoom levels so they're not overpowering at
lower zoom levels.
This doesn't really do all that great a job; Leaflet doesn't really seem
to be equipped to do this well (or, more likely, I'm just not figuring
out how to do it!).
The hack with the extra container is necessary because the transform on
the `.leaflet-map-pane` element creates a new stacking context, which
messes up even `position: fixed`. I wasn't able to figure out a way to
get around this.
Written on an airplane without an internet connection, so per the XKCD
I'd link but can't, "my apparent IQ goes down like 30 points when
[I don't have docs handy; orig "Wikipedia is down"]"!
