bug(Shape): Fix some properties not persisting correctly when modified

[Kruptein]

This fixes #1484

PA tracks internally which shapes are currently selected and the most prominent location of changes of this selection occur when you use the select tool to click on other shapes or deselect the active shape.

Before this PR, the select tool would immediately update the selection state when the mouseDown event is fired. This PR changes this behaviour to wait until mouseMove or mouseUp.

When you're editing for example the name of a shape and you directly click on another shape or even just the map (causing a deselect), a bunch of browser events are fired. First the mouseDown event fires, which until now changed the selection info immediately, then the change event fires, which indicates that the name input field changed content and finally mouseUp is fired.

As you can see by the time the change event hits, we've already changed our selection to either a different shape or cleared the selection info. Which in turn means that the updateName function either changes the name of the wrong shape or simply doesn't have any shape to update.

By delaying the selection change to mouseMove or mouseUp, we're ensuring that these events still operate on the originally selected shape.

Some of you might wonder why the other input field (i.e. 'value') mentioned in the related ticket was working correctly before these changes. That's because that field is still using a legacy way to detect which shape is active that reactively watches the main selection system. This legacy system was getting its update a tick later which happens to be after the change event fired.