pcb_keepout changes

[seveibar]

• rect/circle should both have .center
• layers should be an array (keepouts can be for multiple layers)

[tscircuitbot]

Aider has created a pull request to address this issue: #41

Please review the changes and provide feedback.

[homie-gg]

This might have already been done via: fix: pcb_keepout changes.

[homie-gg]

Here are some pull requests that might be helpful reference for this task:

• feat: add keepout props
• add pcb_keepout as obstacles
• added keepout