* Non-crossing infill optimization
* test triangles
* test grid
* cleaning
* Align and clip rectilinear infill paths
Generate infill coverage in the pattern's local frame, rotate triangular patterns by layer, and clip centerlines to the surface vicinity. Start closed outlines outside the surface so clipping splits them cleanly.
* Update test_fill.cpp
* Update multiline-infill.md
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Co-authored-by: Ian Bassi <ian.bassi@outlook.com>