QML UI: tap on the very top / title bar of dive list goes to top

This requires changes to Kirigami that aren't upstream, yet. So there's
a chance that this commit will have to be changed or reverted / redone.

Signed-off-by: Dirk Hohndel <dirk@hohndel.org>

qt-mobile/qml/DiveList.qml

@@ -263,6 +263,20 @@ Kirigami.ScrollablePage {
 				}
 			}
 		}
+		Connections {
+			target: header
+			onTitleBarClicked: {
+				// if we can see the dive list and it's not at the top already, go to the top,
+				// otherwise have the title bar handle the click (for bread-crumb navigation)
+				if (stackView.currentItem.objectName === "DiveList" && diveListView.contentY > Kirigami.Units.gridUnit) {
+					diveListView.positionViewAtBeginning()
+					event.accepted = true
+				} else {
+					event.accepted = false
+				}
+			}
+		}
+
 	}
 
 	property QtObject addDiveAction: Action {