Remove polygons, introduce SKPath CU-86c3mbjx8

[big-nacho]

Description:

This PR updates the pipeline so that now:
trace -> convert to polygons -> perform boolean operations -> convert back to paths -> generate markup
is
trace -> perform boolean operations -> generate markup

This makes results much better and reduces path complexity a lot.

• I have self-reviewed this PR, according to these points
• This PR falls into maximum three of these categories
• I feel comfortable taking responsibility for merging this code to production
• The code is high quality, well-tested, follows styles guides (Frontend), clean, and well documented