[Feature suggestion] Add the weather prediction to the calculation

Typically, when it's rainy (maybe snowy as well; can't test in Israel), the sky will become darker earlier due to many clouds being together across a wide area
Currently, to combat this I need to manually specify a large offset (the other day it was as much as -66 minutes), but it isn't reliable, as in Israel the next day might be sunny, thus the sky will turn dark later

I believe that the calculation shouldn't be hard: If it's predicted to be rainy (e.g. showers), offset the time to the rain time if it's close to the afternoon (e.g. 3 PM)

The issue names no files, tests, or weather service. Start by locating the existing dark-mode timing calculation and determine how forecast data could be obtained; done would require a defined rainy-weather adjustment that behaves predictably across changing forecasts.

Written by the indexing model from the issue text.