Give solid.move the copy half of its Move/Copy label (#498)

solid.move takes copy: true to keep the source bodies and transform a new copy of each, with a Create Copy box in the Move dialog. Designs without it save and load exactly as before.

crates/engine/src/cmd/features.rs

@@ -107,7 +107,7 @@ pub static COMMANDS: &[CommandSpec] = &[
         .icon("presspull")
         .key("Q")
         .params("face: [x,y,z] and distance: expr (positive adds material, negative cuts), or edges: [[x,y,z]…] and distance (a fillet)"),
-    CommandSpec::new("solid.move", "Move/Copy", move_bodies).at("SOLID", "MODIFY").icon("move").key("M").params("bodies: [names]; translate?: [x,y,z] (exprs or numbers); axis?: [x,y,z]; angle?: expr"),
+    CommandSpec::new("solid.move", "Move/Copy", move_bodies).at("SOLID", "MODIFY").icon("move").key("M").params("bodies: [names]; translate?: [x,y,z] (exprs or numbers); axis?: [x,y,z]; angle?: expr; copy?: bool (default false: keeps the original bodies and transforms a new copy instead of moving them in place)"),
 ];
 
 /// Where an extrude starts and which way is positive: a point inside the (first) profile or
@@ -875,7 +875,11 @@ fn move_bodies(s: &mut Session, p: &Value) -> Result<Value> {
     if let Some(a) = &angle {
         check_expr(s, a, Kind::Angle, cmd, "angle")?;
     }
-    add_feature(s, p, FeatureKind::Move { bodies, translate: t, rotate_axis: p.get("axis").and_then(vec3), angle })
+    add_feature(
+        s,
+        p,
+        FeatureKind::Move { bodies, translate: t, rotate_axis: p.get("axis").and_then(vec3), angle, copy: bool_(p, "copy").unwrap_or(false) },
+    )
 }
 
 fn source_features(s: &Session, p: &Value, cmd: &str) -> Result<Vec<String>> {
@@ -1536,3 +1540,7 @@ mod offset_plane_face_tests;
 #[cfg(test)]
 #[path = "stacked_face_tests.rs"]
 mod stacked_face_tests;
+
+#[cfg(test)]
+#[path = "solid_move_copy_tests.rs"]
+mod solid_move_copy_tests;