Add scroll hints to the cross-animation blend dialog

[YeldhamDev]

[TokageItLab]

I saw differences in the modern theme although I'm unsure what's different in the classic theme. If changes are to be applied, and if they are related to animation, I believe changes would also be needed in the AnimationLibraryEditor.

It seems you might be picking up things that were forgotten to be applied when the scroll hint was implemented previously. I think it would be better to have a single PR that finds and applies all necessary changes in other places, not just for animations, in case such places exist.

As I mentioned above, I won't approve this immediately because I think it need consistency regarding Animation, at least concerning the AnimationLibraryManager, but I don't see any problem with merging this itself.

If you are going to create a comprehensive PR that applies to areas other than Animation, it would be good to have someone very familiar with the modern theme review it.

[YeldhamDev]

I saw differences in the modern theme although I'm unsure what's different in the classic theme.

Scroll hints are only available for the modern theme.

If changes are to be applied, and if they are related to animation, I believe changes would also be needed in the AnimationLibraryEditor.

There's already a PR for that: #115038

It seems you might be picking up things that were forgotten to be applied when the scroll hint was implemented previously. I think it would be better to have a single PR that finds and applies all necessary changes in other places, not just for animations, in case such places exist.

Those are the only places left that I can think of that need hints.

I can unify the two PRs if you want, but I don't see what much this achieves besides giving me more work for little to no gain. And I'm already busy as is with the GridMap tasks.

[Repiteo]

Thanks!