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 <william.dunn@quasarke.com>

crates/ui-egui/src/viewport.rs

@@ -855,7 +855,7 @@ fn pick_hits(app: &SolveApp, proj: &Proj, pos: Pos2, other_sketch_points: bool,
         let Some(ss) = st.sketch(sid) else { continue };
         let bonus = if s.active_sketch == Some(sid) { 2.0 } else { 0.0 };
         for (i, c) in ss.sketch.curves.iter().enumerate() {
-            if c.link.is_some() && ss.sketch.view.hide_projected {
+            if !solidcraft_engine::view::sketch_curve_visible(&ss.sketch, i) {
                 continue;
             }
             let straight = matches!(c.kind, CurveKind::Line { .. });
@@ -2493,7 +2493,7 @@ fn box_select(app: &mut SolveApp, proj: &Proj, bx: BoxSel, add: bool) {
         // What the selection filter lets through (window: wholly inside; crossing: touching).
         let off = |k: &str| app.ui.pick_off.iter().any(|x| x == k);
         for (i, c) in ss.sketch.curves.iter().enumerate().filter(|_| !off("sketch") && !off("sketch_curves")) {
-            if c.link.is_some() && ss.sketch.view.hide_projected {
+            if !solidcraft_engine::view::sketch_curve_visible(&ss.sketch, i) {
                 continue;
             }
             let sampled = if bx.crossing {