Bug: icondiff show incorrect diffs

[Dimach]

Here it show almost entire file changed, and icons shuffled randomly ss220-space/Paradise#3342
Here it shows chnages in nianflag_fire (flags_lefthand.dmi, flags_righthand.dmi) when there was no changes, also it show wrong animation ss220-space/Paradise#3354
When DMI files not contains animation behavior looks correct

[GoldenAlpharex]

I have another instance of this:
https://github.com/Skyrat-SS13/Skyrat-tg/runs/16449958042

It seems as though it's not parsing the amount of frames properly, and is shifting some frames around on accident, when there's some mix between animations and non-animations within the same file.

[volas]

Happens often for us too, especially with some files with multiple states like inhands

https://github.com/TauCetiStation/TauCetiClassic/pull/12395/checks?check_run_id=19014059257
https://github.com/TauCetiStation/TauCetiClassic/pull/12408/checks?check_run_id=18995540656

[ZeWaka]

example
https://github.com/goonstation/goonstation/pull/17340/checks?check_run_id=19696891644

[volas]

I think it's fixed in #30

fixes reading the wrong frame number from the wrong number of delays