fix: refuse Boolean retries that change the part away from the tool (#616) (#644)

Joining ribs flush with a lid's window left a zero-thickness slit far from the rib (the planar fallback glued back only one of the faces its pieces shared) and displaced the tool on the other joins. Gluing now joins every shared face pair, coincident-face separation checks there is material behind a pushed face for every join, and any join or cut that needed a retry must be closed, keep volume monotonic and leave the part unchanged outside the tool's box, or it is refused with an error. Feature command replies carry the feature's warning.

Co-Authored-By: Claude Opus 5.5 <[email protected]>

crates/engine/src/cmd/features.rs

@@ -483,8 +483,11 @@ fn add_feature_in(s: &mut Session, p: &Value, kind: FeatureKind, world: bool) ->
         st.bodies.iter().filter(|b| b.feature != id && old.get(b.name.as_str()).is_some_and(|o| !o.same(&b.body))).map(|b| b.name.as_str()).collect();
     let removed: Vec<&str> = before.bodies.iter().map(|b| b.name.as_str()).filter(|n| !now.contains(n)).collect();
     let fname = s.doc.feature(id).map(|f| f.name.clone()).unwrap_or_default();
+    // A warning (a Boolean that needed a retry, a reference found again elsewhere) is part of
+    // the reply: a script or an agent sees it without asking the timeline (#616).
+    let warning = r.as_ref().and_then(|r| r.warning.clone());
     Ok(json!({"feature": id, "name": fname, "bodies": bodies, "created_bodies": created, "changed_bodies": changed,
-        "removed_bodies": removed, "ms": r.map(|r| r.ms)}))
+        "removed_bodies": removed, "warning": warning, "ms": r.map(|r| r.ms)}))
 }
 
 fn extrude(s: &mut Session, p: &Value) -> Result<Value> {