3D and Materials: Expand as Wireframes expands an id given twice once

An object or layer named twice in ids is expanded once, so the selection holds only the edges that are in the document.

crates/engine/src/cmd/wireframe.rs

@@ -47,7 +47,12 @@ fn expand_as_wireframes(s: &mut Session, p: &Value) -> Result<Value> {
     // they are.
     let d = &s.doc()?.doc;
     let mut wires = vec![];
+    let mut seen = std::collections::HashSet::new();
     for id in roots {
+        // An id given twice is expanded once.
+        if !seen.insert(id) {
+            continue;
+        }
         let Some(n) = d.node(id) else { continue };
         if !effects::has_revolve(n) && !effects::has_solid(n) {
             continue;

crates/engine/src/cmd/wireframe/tests.rs

@@ -71,7 +71,8 @@ fn a_layer_with_a_3d_effect_stays_a_layer_holding_the_edges() {
     let layer = s.doc().unwrap().doc.layers[0].id;
     s.execute("effect.apply", &json!({"ids":[layer.0],"effect":"threeD.extrude","item":null,"params":{}})).unwrap();
     let history = undo_len(&s);
-    let out = run(&mut s, json!({"ids":[layer.0]})).unwrap();
+    // An id given twice is expanded once.
+    let out = run(&mut s, json!({"ids":[layer.0, layer.0]})).unwrap();
     assert_eq!(out["ids"], json!([layer.0]));
     let st = s.doc().unwrap();
     let node = st.doc.node(layer).unwrap();