Workspace improvements: hover states and animate in

[timoni]

Workspaces UI should include more animations and highlights to indicate when objects are being made, manipulated, or destroyed.

When a ListItem is created, it should:

• briefly animate in the list (scale from center)
• have a brief highlight based on the session gradient
• go from 0% to 100% opacity

Also:

• Objects in the list should animate up or down to make room.

We can adjust timing, but think .1-.3 seconds.