Calibration: Improve UI 2

Large vehicle calibration is working fine! :)

one annoying thing: the "Current Declination", which doesn't show the current declination, rather, it seems to be showing the last manual declination set.

It's weird to have to input the declination in a separate window if I can select the value. Maybe make it non-selectable, but also, make something like a transparent text that shows when the mouse hovers it saying "CLICK TO EDIT", to indicate the action.

Also about it, the edit box contains units, and the main "current declination" value does not.

Another thing is: why can't I manually enter the GPS coordinates?

_Originally posted by @joaoantoniocardoso in https://github.com/bluerobotics/BlueOS/pull/2342#pullrequestreview-1860369752_