Add "2D Lattice" fill pattern for lightweight aircraft structures (#8293)

* Add 2D lattice infill pattern

* Add state invalidation behavior for lattice infill angles

* Update SurfaceFillParams methods to account for lattice infill angles

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Co-authored-by: SoftFever <softfeverever@gmail.com>
Co-authored-by: Noisyfox <timemanager.rick@gmail.com>

src/libslic3r/Layer.cpp

@@ -391,6 +391,7 @@ coordf_t Layer::get_sparse_infill_max_void_area()
                 max_void_area = std::max(max_void_area, spacing * spacing);
                 break;
             case ipGrid:
+            case ip2DLattice:
             case ipHoneycomb:
             case ipLightning:
                 max_void_area = std::max(max_void_area, 4.0 * spacing * spacing);