feat: improve UI/UX of builder

[techfg]

Currently, the "props" for a component are on the far left of the screen while the component index is on the far right. Especially on wide screens, this makes editing/configuring more difficult than necessary since a user is always having to move from far left to far right for a single "action" (e.g., set/view properties of a component).

Possibly consider moving the component index to the left, beside the left nav panel.

In a perfect world, I think the following would be ideal:

1. All panels are dockable and can be moved by the user to their preferred location
2. All panels can be expanded/collapsed
3. All panels can be shown/hidden
4. All panels (except the main canvas) can "pop-out" to increase canvas size