Construction Geometries, a Sketch Palette row that hides construction geometry (#804)

A Sketch Palette toggle (sketch.options show_construction) that hides construction geometry from drawing and picking; saved with the sketch's view options under format 17.

Co-authored-by: William Dunn <[email protected]>

crates/doc/src/format.rs

@@ -100,6 +100,8 @@
 //!   Under the same version, a sheet metal rule's corner relief shape can also be `tear` (no
 //!   relief: each bend is cut straight from the bends' corner to where its flange's end
 //!   starts); a rule that says `notch`, `round` or `rectangular` builds what it did.
+//!   A sketch's view options can also say `hide_construction` (the Sketch Palette's
+//!   Construction Geometries); a sketch that shows its construction geometry saves as before.
 //!   A `SurfaceExtrude` feature (Surface Extrude: `sketch`, optional `profiles`, `curves` and
 //!   `extent`, walls only) is first saved in 17; 0.8.0 would refuse the unknown feature.