Time of arrival does not take into account time zone changes

Source thread: https://discord.com/channels/1313185644134006886/1320306766830895167

> Basically, if you start a trip that spans time zones, the mile count, and time of travel are both correct, but the time of arrival is based upon your current time + time of travel, and therefore if your route crosses time zones, it will not display the correct time of arrival until you are in the destination time zone

Start with the time-of-arrival calculation and reproduce a trip that crosses time zones, using the linked Discord source thread for context. Compare the displayed arrival time with the destination's local time during the trip; done means the arrival time is correct before reaching the destination time zone.

Written by the indexing model from the issue text.