mesh: node tools commands: merge, duplicate check, renumber (#234)

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

crates/engine/src/catalogue.rs

@@ -357,7 +357,14 @@ pub static CATALOGUE: &[Capability] = &[
     ready_more("mesh.node.add", "Node", Mesh, "Edit", "Add a node", &["mesh.node.remove"]),
     ready_more("mesh.element.add", "Element", Mesh, "Edit", "Add an element on existing nodes", &["mesh.element.remove"]),
     ready("mesh.mirror", "Mirror Mesh", Mesh, "Edit", "Mirror a body's mesh across a plane, joined on the plane (mesh half a symmetric part)"),
-    soon("mesh.node.merge", "Merge Nodes", Mesh, "Edit", "M6", "Merge coincident nodes"),
+    ready_more(
+        "mesh.node.merge",
+        "Merge Nodes",
+        Mesh,
+        "Edit",
+        "Merge coincident nodes, keeping sets, loads and boundary conditions on the survivors; check for duplicates and cracks, renumber",
+        &["mesh.check.duplicates", "mesh.renumber"],
+    ),
     soon("mesh.region.remesh", "Remesh Region", Mesh, "Edit", "M6", "Remesh a region in place; split and collapse elements"),
     soon("mesh.import.orphan", "Orphan Mesh", Mesh, "Edit", "M6", "Import a mesh without geometry"),
     ready("mesh.quality", "Quality", Mesh, "Verify", "Quality metrics and the certified validity check, failing elements listed"),