Confirm cross-section device moves

tests/circuit-grid-safety.test.ts

@@ -3,6 +3,7 @@ import { describe, it } from "node:test";
 import {
   findDuplicateEquipmentIdentifierCircuitIds,
   hasEquipmentIdentifierConflict,
+  requiresCrossSectionMoveConfirmation,
   resolveGridDeleteIntent,
 } from "../src/frontend/utils/circuit-grid-safety.js";
 
@@ -76,4 +77,11 @@ describe("circuit grid safety", () => {
       ["a", "b"]
     );
   });
+
+  it("requires confirmation when any moved device crosses a section boundary", () => {
+    assert.equal(requiresCrossSectionMoveConfirmation(["single"], "single"), false);
+    assert.equal(requiresCrossSectionMoveConfirmation(["single", "single"], "single"), false);
+    assert.equal(requiresCrossSectionMoveConfirmation(["single"], "three"), true);
+    assert.equal(requiresCrossSectionMoveConfirmation(["single", "three"], "three"), true);
+  });
 });