fix: detect multiple animations

[navorite]

trims whitespace while at it, closes #10189

the first change fixes it, but I thought improving the parser whitespace handling for this case would be better and more consistent since we use it in the analyzing step, added a test case for both changes.

we can also prevent appending the magic string to the animation name if it is inside a comment

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🦋 Changeset detected

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[navorite]

closing in favor of #10432