feat(web): copiar de / a entre documentos de ventas y compras

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

apps/web/src/app/features/documents/document-model.spec.ts

@@ -91,6 +91,16 @@ describe('createPayload', () => {
     expect(body['DocumentLines']).toEqual([{ ItemCode: 'A1', Quantity: 1, DiscountPercent: 0 }]);
   });
 
+  it('envía la referencia al origen solo en las líneas copiadas', () => {
+    const body = createPayload({ CardCode: 'C1' }, [
+      line({ BaseType: 17, BaseEntry: 315, BaseLine: 0 }),
+      line({ BaseType: -1, BaseEntry: null, BaseLine: null }),
+    ]);
+    const [copied, own] = body['DocumentLines'] as Record<string, unknown>[];
+    expect(copied).toMatchObject({ BaseType: 17, BaseEntry: 315, BaseLine: 0 });
+    expect(own).not.toHaveProperty('BaseType');
+  });
+
   it('isBlankLine', () => {
     expect(isBlankLine({ ItemCode: '' })).toBe(true);
     expect(isBlankLine({ ItemCode: 'A1' })).toBe(false);