[Geometry tasks] Enforce min. device location distance threshold

[gino-m]

Summarizing from #2565:

• Min. threshold will be optionally specified by survey organizers.
• The threshold is enforced only when location lock is enabled
• For "Capture Location", location lock is always on, so the threshold always applies.

Given this feature, I suspect we'll also want to somehow combine "Drop a pin" and "Capture location", that way the organizer's workflow will be more understandable, but that's out of scope of this FR.

@vittorino Do you have cycles to draft designs for the organizer and data collector? Full discussion was in #2565.