Adds a 'stamp mode' which behaves exactly like center dragging but commits the shape upon left clicking instead of putting down the shape.

Adds a 'shape' which just returns it's marks as being part of the shape.

Makes the ctrl+v shortcut create a Point Drawing shape that mimics the shape of the designated tiles under the current shape, then immediately starts stamp mode.

… designation.

It may be necessary to reaffirm the need to disable auto-commit to use the feature in the tool, but I hope that player's curiosity in "copy designated tiles" will suffice.