Implement AnimatedSprite pause() and resume()

[madmiraal]

As originally identified by in #31168,

Right now, the method stop() in AnimatedSprite is working as a pause (it is even stated in the documentation saying it doesn't reset the frame counter)

As suggested in godotengine/godot-proposals/issues/#287, to make AnimatedSprite2D and AnimatedSprite3D interfaces the same as AnimationPlayer (and ideally AudioStreamPlayer, VideoPlayer and Tween) this PR implements pause() and resume(), and updates the play() and resume() methods in AnimatedSprite2D and AnimatedSprite3D to be consistent with the changes made to AnimationPlayer in #44345 #56645 including:

• Ensuring that play() always plays the specified (or current animation) from the beginning (or end if playing backwards) regardless of whether or not the requested animation is the same as the current animation
• Ensuring that stop() also resets the animation
• Updating the relevant documentation

Part of #16863

[madmiraal]

Updated to include renaming play() to start() to align with the changes made to #44345.

[madmiraal]

Rebased following merge of #47064.

[madmiraal]

Rebased following merge of #47645.

[reduz]

Give the new process modes in master, I think there is probably not a lot of merit for having this? other than maybe usability.

[madmiraal]

Pausing (and unpausing) the entire SceneTree is not a convenient or even a realistic way of pausing and resuming an AnimatedSprite's playing animation.

[KoBeWi]

Pausing (and unpausing) the entire SceneTree is not a convenient or even a realistic way of pausing and resuming an AnimatedSprite's playing animation.

That was the point of the pause rework. You don't need to pause entire scene tree, just set process_mode of a node to PROCESS_MODE_DISABLED to pause it. It does affect the children too, but AnimationPlayer with child nodes is rather rare.

[madmiraal]

It's worth stressing that, as detailed in the OP this PR is not about creating pause functionality (stop already does that). It's about having four methods: start(), stop(), pause() and resume() that behave as expected and consistently across all players. See #56645 for the AnimationPlayer version.

[KoBeWi]

I understand stop() and pause(), but what is the point of start() and resume()? Both methods are covered by play(), it just depends on whether you stopped or paused the animation before playing.

[madmiraal]

• start(): Always plays the animation from the beginning (or the end if backwards is true).
• resume() Continues playing the animation from where it was paused.

[KoBeWi]

I know what they do, but if you want to restart animation, you can just do stop() and then play(). Or pause() play() to resume from a point. start() basically duplicates stop(). It's redundant.

[clayjohn]

Discussed in PR review. It appears there is no consensus that the proposed API is any easier for users than the old API. Accordingly, the current approach should be documented more clearly to describe when it will restart vs just start/stop the animation.