Shared animation library

[TheDuckCow]

The idea is to create a library of animation presets for MCprep rigs which can be used for quick animations. This is a long term feature which would require some thought and time to implement.

There are a few ways to implement this:

• Include an "actions" file within MCprep which contains pre-created actions. Simplest and would work as another library file, ensuring that all actions are set with "fake users" so they are not removed.
• Create a backend as well as addon integration to storing plain text structure version of actions, so that users can create and share actions with other users and be updated asynchronously to MCprep itself. Much more initial code setup and requires a functional backend to read from (though this functionally already exists for MCprep), but removes the bottleneck of centrally updating actions and limiting them to the same cadence of updates as MCprep itself.

Additional considerations: Consider going through MCprep mob and ensuring consistency of bones bones for main/torso/arms/legs. Though not too likely to be able to directly copy an animation from one rig to another, worth at least attempting compatibility in case multiple rigs are derived from

This also requires some mechanism of applying an action library, would could behave in a few ways on its own:

• Add actions as an NLA strip (pushing down anything that already exists) and adding the new action starting at the current time cursor.
• A function which replaces or blends in the selected action starting at the current time frame, possibly with a modal to define how often to repeat it (if at all), likely also with option for whether it should blend or clear prior keyframes