优化编号讲解布局与返回流程

- 将讲解编号置于标题上方并增强辨识度
- 编号详情返回后保留输入界面并清空原编号
- 增加页面栈丢失时恢复编号输入页的兜底逻辑
- 补充编号布局和返回流程回归测试

Made-with: Proma

tests/unit/ExplainGuideStopCatalog.spec.ts

@@ -24,6 +24,9 @@ describe('ExplainGuideStopCatalog', () => {
     expect(wrapper.text()).toContain('图文')
     expect(wrapper.get('.stop-code').text()).toBe('编号：0231')
     expect(wrapper.findAll('.stop-code')).toHaveLength(1)
+    const readyCopy = wrapper.get('.stop-card .stop-copy')
+    expect(readyCopy.element.firstElementChild?.classList.contains('stop-code')).toBe(true)
+    expect(readyCopy.element.lastElementChild?.classList.contains('stop-name')).toBe(true)
     expect(wrapper.text()).not.toContain('暂无内容')
     expect(wrapper.find('.hall-arrow').exists()).toBe(false)
     expect(wrapper.find('.stop-name').classes()).toContain('stop-name')