feat: expose Construction Line in the Draw expansion

src/modules/draw/draw/ray.rs

@@ -167,7 +167,6 @@ impl CadCommand for XLineCommand {
                 Vector3::new(base.x, base.y, base.z),
                 Vector3::new(dir_n.x, dir_n.y, dir_n.z),
             );
-            self.base = None;
             CmdResult::CommitEntity(EntityType::XLine(xline))
         } else {
             self.base = Some(pt);

src/ui/ribbon/draw_tools/03_xline.rs

@@ -0,0 +1,6 @@
+Tool {
+    command: "XLINE",
+    label: "Construction Line",
+    icon: include_bytes!(concat!(env!("CARGO_MANIFEST_DIR"), "/assets/icons/xline.svg")),
+    options: &[],
+}