This patch makes the internal functions for the pose library aware of action slots.
* Allows to apply poses with more than 1 slot.
* The slot is chosen based on a best guess, with a fallback to the first slot.
Not in this patch:
There is no straightforward way to create multi slot pose assets yet. That will come later.
It is possible to manually tag an action with more than 1 slot as an asset though.
When applying poses, only the active object is modified. Multi object editing support will come later.
Part of Design #131840
Pull Request: https://projects.blender.org/blender/blender/pulls/132161
c3e5d15c2e