Method testDuplicateAddsOneNode

tests/test_context_menu.cpp:123–137

    // ── Duplicate creates exactly one copy ──

    void testDuplicateAddsOneNode() {
        int flagsIdx = findNode("flags");
        QVERIFY(flagsIdx >= 0);
        int before = countNodes();

        m_ctrl->duplicateNode(flagsIdx);
        QApplication::processEvents();

        QCOMPARE(countNodes(), before + 1);

        int copyIdx = findNode("flags_copy");
        QVERIFY2(copyIdx >= 0, "Expected a node named 'flags_copy'");
        QCOMPARE(m_doc->tree.nodes[copyIdx].kind, NodeKind::Hex32);
        QCOMPARE(m_doc->tree.nodes[copyIdx].offset, 16);  // flags(12) + 4 = 16
    }

    // ── Duplicate preserves original node unchanged ──