Fix location change overriding recent region changes (#1640)

Fixes #1620.

## Summary
Prevents doing a location update just after a region event -- within 30 seconds. Region events may have accuracy fuzzing which the significant location change wouldn't know about, so it would override the fuzz. Region events are never prevented.

## Any other notes
This also makes processor events queue up rather than all executing simultaneously, both so we can make sure we don't do this error case and so we don't have other weird state transitions that I can't think of.

Sources/App/ClientEvents/LocationHistoryDetailViewController.swift

@@ -115,6 +115,7 @@ final class LocationHistoryDetailViewController: UIViewController, TypedRowContr
             ```
 
             ## Location
+            - Trigger: \(entry.Trigger ?? "(unknown)")
             - Center: (\(latLongString(entry.Latitude)), \(latLongString(entry.Longitude)))
             - Accuracy: \(distanceString(entry.Accuracy))\(accuracyNote)
             - Accuracy Authorization: \(accuracyAuthorization)