Export animated models

Hi,
Congratulation for the project, is amazing how simple and effective this technic is.
The only problem that I found is the difficult is export animated model to use in other game engines, like Phaser 3 JS. A export helper that save all the animation in PNG frames would be very helpful for that job.
For while, I having a lot of pain saving my model using _right click_ and _save as..._ .

One again, great project, I'm very excited to try draw new things.

Start by examining the existing right-click “Save as...” export flow for animated models and how animation frames are represented. Define the export behavior around the requested Phaser 3 use case, with completion meaning all animation frames can be saved as PNG files for use in another engine.

Written by the indexing model from the issue text.