Wall overrides

[ikeough]

This is a continuation of the work started by @nadiia-volyk in #46. It updates that branch's work to master and updates the code to use RoomEdge where applicable, and to convey Thickness throughout all parts of the code which create wall candidates.

The following additional updates are still required:

• Update code to not use an add override for lines. This was originally added for wall splitting, but is de-prioritized.
• Update de-duplication code to use thickness. Currently if this code is enabled, we get dropped walls.

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This change is