Emit changed signal on SpriteFrames for animation changes.

[hworld]

Currently only the frame-related updates emit the changed signal. This changes it to also emit for changes in the animations, such as adding an animation, renaming, setting loop, etc.

[Chaosus]

Not sure if this is safe to introduce to 4.x - users may wonder why that signal start to emitted for simple operations (which may cause unwanted effects for the existed projects).

Also - CI failed, you need to fix it (use clang-format next time to prevent this from happen) and squash the commits (see https://docs.godotengine.org/en/latest/contributing/workflow/pr_workflow.html#modifying-a-pull-request)