[2.0.49] AnimationSheet.repeat_count is not handled properly

[Hanodest]

Demonstration of the problem:

animation_sheets.mp4

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Two similarly defined entities. Both use main animation with frame_count=32, and an animation with frame_count=1 repeat_count=32 for the shadow.
The left one has its animation defined as animation with two layers. The right one uses sheets instead.

Expected behavior: shadow is drawn continuously for both entities.
Actual behavior: for the right entity the shadow is drawn 1 frame out of 32.

If there's only one sheet with repeat_count, then the game crashes on the entity being placed.

In attachments: the mod that defines these two entities and the save shown in the video.
Version 0.1.0 of the mod should show the visual problem when loading the save
Version 0.2.0 of the mod should crash the game when loading the save.