Survey UI: Less clicks to make a survey mission

If you make a survey before creating a polygon you are prompted to load one from file, and told to draw one if you click 'No'


Suggestion
1. Rt click > Auto WP > Survey automatically makes a polygon centered at home with 4 sides, 200m on a side, if a polygon has not yet been created
2. If that's not possible, auto enter into polygon mode rather than prompting to draw a polygon

Start by reproducing the right-click > Auto WP > Survey flow when no polygon exists, then inspect where the load-from-file prompt and polygon drawing mode are triggered. Done means Survey can create the described centered four-sided 200 m polygon automatically, or enters polygon mode directly instead of prompting to load one.

Written by the indexing model from the issue text.