model: geometry names up to 64 KiB everywhere, so long persistent face names mesh

Persistent names grow with a design's split history; opening accepted them but mesh tags, sets
and loads capped geometry names at 256 characters. One cap (64 KiB, against hostile input)
now holds for geometry references, partitions and saved views.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01UhhZMBTviDQxZvwnyP89fo

crates/engine/src/cmd/mesh.rs

@@ -896,6 +896,35 @@ mod tests {
         assert!(e.starts_with("body `Box"), "{e}");
     }
 
+    /// Persistent names grow with the design's split history: a tray floor split by joined ribs
+    /// names every split, past the old 256-character cap. Such a design meshes, and a set on that
+    /// face resolves by its full name, again after a remesh (#374).
+    #[test]
+    fn long_persistent_face_names_mesh_and_resolve() {
+        let mut commands = vec![
+            json!({"command": "solid.box", "params": {"length": 40, "width": 30, "height": 20, "corner": [0, 0, 0], "body_name": "Case"}}),
+            json!({"command": "solid.shell", "params": {"faces": [[20, 15, 20]], "thickness": 2, "direction": "inside", "body": "Case"}}),
+        ];
+        // Ribs across the floor split it into strips, each named by every split before it.
+        for x in (3..=36).step_by(3) {
+            commands.push(json!({"command": "solid.box", "params": {"length": 1, "width": 26, "height": 5, "corner": [x, 2, 2], "operation": "join", "targets": ["Case"]}}));
+        }
+        let bytes = fieldcraft_geometry::script_design(&json!({"commands": commands}).to_string()).unwrap();
+        let (_dir, path) = crate::tests::design_file(&bytes);
+        let mut s = Session::default();
+        s.execute("geometry.open", &json!({"path": path})).unwrap();
+        let bodies = s.execute("geometry.bodies", &json!({})).unwrap();
+        let long = bodies[0]["faces"].as_array().unwrap().iter().filter_map(|f| f["name"].as_str()).max_by_key(|n| n.len()).unwrap().to_string();
+        assert!(long.len() > 256, "the fixture needs a face name past the old cap: {long}");
+        s.execute("mesh.tet.generate", &json!({"body": "Case"})).unwrap();
+        s.execute("model.set.create", &json!({"name": "floor", "geometry": [{"body": "Case", "face": long}]})).unwrap();
+        let first = s.model.resolve_set("floor").unwrap();
+        assert!(!first.faces.is_empty());
+        s.execute("mesh.tet.generate", &json!({"body": "Case", "tolerance": 0.5})).unwrap();
+        let again = s.model.resolve_set("floor").unwrap();
+        assert!(!again.faces.is_empty(), "the set follows the remesh by the full name");
+    }
+
     /// The quality report's one-line summary counts the inverted elements.
     #[test]
     fn quality_summary_counts_invalid_elements() {