Add a Selected Tile Preview to "Shape Fill Tool", just like the "Stamp Brush" has

Is your feature request related to a problem? Please describe.
I like using the rectangular paint in tilemap editors. It allows for easier control and, also, in Tiled, the rectangular Shape Fill Tool properly repeats the pattern of multiple-selected-tiles when drawing, unlike the Stamp Brush.
But, there's a big problem with the rectangular paint ("Shape Fill Tool") in Tiled: you cannot see a preview of what tiles you have selected.
The default free-draw tool ("Stamp Brush") has a preview of selected tiles that follows the cursor; the Shape Fill Tool does not have this, and therefore you cannot see if the tiles are rotated or mirrored until after painting them. You also have no visualization of how the tiles will be placed down on the map without any preview.

Describe the solution you'd like
Just like the Stamp Brush, it'd be great if the Shape Fill Tool could have a selected-tiles preview that follows the cursor. Perhaps this could be resolved by reusing Stamp Brush preview code for the Shape Fill Tool? (I'm not sure, as I am not really a programmer).

Describe alternatives you've considered
There are no alternative solutions, aside from just dealing with the confusion that having no preview creates, or using Stamp Brush instead of Shape Fill Tool, neither of which are ideal.

I truly believe that implementing a preview for the Shape Fill Tool would improve user experience.
Thank you for reading my request.

Start by locating the Stamp Brush preview and Shape Fill Tool implementations in the Tiled editor. Compare how the selected tiles, rotation, and mirroring are represented, then determine how a preview can follow the cursor for Shape Fill Tool. Done means the selected-tile pattern is visibly previewed before painting, including transformations.