SAS Direction / Target Hold gets reset on vessel focus

[HB-Stratos]

Provide a description of the KSP bug or improvement

This is a pretty simple one, likely originally intended behavior. When one selects target hold on a Vessel, it keeps holding that target even if the player switches away from it. However, as soon as that Vessel is re-focussed, the SAS resets to stability assist.

I find this quite annoying as I often work with vehicles (missiles) that use target hold for their aiming. They do not need to be interacted with, but if I quickly swap through vessels to find the target or the launching plane and cross a missile on the way, its SAS hold is reset.

As it is as easy as pressing "F" to reset the SAS back to stability assist intentionally, I would argue the auto-reset behavior can be removed.