Animation: Blur and shrink on delete/collapseContext

[raineorshine]

• Blocked by: Animation: Fade out unmounted thought #2526

Steps to Reproduce

- a
- b
- c

Delete b.

Current Behavior

b fades out according to the default unmount animation.

Expected Behavior

The thought should fade out, blur, and shrink (scale3d) when the following commands are executed:

• Delete
• Collapse Context

[raineorshine]

@zukilover Could you limit the fade/shrink/blur animation to the delete and collapseContext commands as requested in the original issue? You'll have to open a new PR as I merged #2596 prematurely.