AnimationTree: OneShot should reset StateMachine internal state upon its completion

[xahon]

Godot version

4.0 dev

System information

Windows 10

Issue description

I have an AnimationTree root blendtree that looks like that:

Here I have a default locomotion animations and an override blending for attack animation to make it possible to both walk and attack at the same time. The problem is that after the very first OneShot's shot my state machine gets its job done and OneShot's shot flag becomes false again but I can't make it true another time because internal state machine's state is set to "exited" (it's my assumption). The only way I could fix this is to recreate AnimationNodeStateMachinePlayback object on the SM node. I'm not sure if it's possible to do from code. It clearly looks like a bug for me. AnimationTree should either have a flag "Reset state machine on exit" or it should do it by default. IMO state machines in animation should behave differently from a regular state machines used for other software. I use a state machine here to make a complex animation logic (Do the first animation, after completion of the first I want to play another looped animation, then I wait for an event or input from user, etc…) and expected it to reset its state each time I call it from a particular node but I don't expect it to be reset while they are doing their job (For example if I trigger OneShot while state machine didn't yet reached the exit node), however, the latter can be handled by the logic in a script

Steps to reproduce

In the attached project:

1. Click on the AnimationTree with name "CLICK ME"
2. Open AnimationTree panel below
3. Click on OneShot's "On"
4. Wait for a second while a dummy animation played (1s)
5. Try activate OneShot again - Immediate reset happens :(

Minimal reproduction project

Issue.zip