weather/noaa: Add a local copy of the station list as a fallback

Reason for the change

The index of noaa stations is now unavailable online.

Yet another piece of tape on the breaking tank, but let's hope it is enough for 6.1, since the full porting to the new API means a harder refactor and I'd like to cherry-pick only the minimal changes possible.

Also fix the observation url path, to avoid needing several redirections.

Test plan

The weather applet works for the noaa provider