Add Polygon Select to the Lasso tool

[Acyone]

Description

When using the lasso tool, crtl-clicking or shift-clicking a point would draw the selection in a straight line from the last selected point to the next.

This would :

• allow selection of polygonal shapes with perfect edges
• make selecting precise shapes easier
• speed up rough selections

Additional context

Discussed in #610

^{Originally posted by enderpuff December 15, 2023}
Pretty self explanatory, but polygon selects are very very useful for editing images, for stuff like isolating objects or removing backgrounds, etc...

[cameronwhite]

Doing this as part of the lasso tool sounds reasonable to me 👍

There could also be an option in the toolbar to switch between the two modes, as an alternative idea to the ctrl/shift hotkeys