fix(ui): sync deployed footer cleanup

Use deployed server source as canonical. Remove the shared legal footer and keep its regression test. Remove four stale temporary test artifacts absent from the server.

frontend/src/__tests__/layouts/DashboardLayout.spec.ts

@@ -137,6 +137,13 @@ describe('DashboardLayout', () => {
     expect(wrapper.find('.dashboard-layout').exists()).toBe(true)
   })
 
+  it('does not render the removed copyright and legal footer', () => {
+    expect(wrapper.find('footer').exists()).toBe(false)
+    expect(wrapper.text()).not.toContain('保留所有权利')
+    expect(wrapper.text()).not.toContain('隐私政策')
+    expect(wrapper.text()).not.toContain('服务条款')
+  })
+
   it('toggles sidebar correctly', async () => {
     const vm = wrapper.vm as unknown as DashboardLayoutInstance
     expect(wrapper.classes()).not.toContain('sidebar-collapsed')