Phase 007: migrate every remaining view from naive-ui to Arco Design Vue

The project now has exactly one UI library. Every naive-ui component in
packages/client/src is replaced by its Arco equivalent across 24 views and
roughly 80 components, and naive-ui is dropped from package.json along with
its transitive vueuc / @css-render / vdirs / seemly dependencies.

The migration is rendering-layer only. No store logic, no API contract, and
no /chat-run payload was touched.

Three classes of leftover were invisible to `grep naive-ui` and are now
covered by tests/client/no-naive-ui.test.ts, which asserts all three:
  - dead .n-* class names in style blocks
  - dead --n-* custom properties
  - naive-ui in package.json

Notable behavioural traps handled along the way, recorded in
docs/arco-migration-rules.md:
  - a-input-password defaults to masked; passing default-visibility="false"
    would have exposed API keys in clear text
  - a-upload fires a real XHR unless auto-upload is false
  - nested Trigger components fight over the first element child, so the
    group-chat settings dropdown was flattened
  - Arco renders tooltip default-slot text inline, which was silently
    collapsing the chat and group-chat toolbars

tests/client/workspace-long-names.test.ts

@@ -2,7 +2,7 @@
 import { beforeEach, describe, expect, it, vi } from 'vitest'
 import { mount } from '@vue/test-utils'
 import { createPinia, setActivePinia } from 'pinia'
-import { defineComponent, h } from 'vue'
+import ArcoVue from '@arco-design/web-vue'
 import FileList from '@/components/hermes/files/FileList.vue'
 import FileTree from '@/components/hermes/files/FileTree.vue'
 import { useFilesStore } from '@/stores/hermes/files'
@@ -12,11 +12,6 @@ vi.mock('vue-i18n', () => ({
   useI18n: () => ({ t: (key: string) => key }),
 }))
 
-vi.mock('naive-ui', async (importOriginal) => ({
-  ...(await importOriginal<typeof import('naive-ui')>()),
-  useMessage: () => ({ error: vi.fn() }),
-}))
-
 vi.mock('@/api/hermes/files', () => ({
   listFiles: vi.fn(),
 }))
@@ -25,44 +20,10 @@ vi.mock('@/api/hermes/download', () => ({
   downloadFile: vi.fn(),
 }))
 
-const NSpinStub = defineComponent({
-  props: ['show'],
-  setup(_props, { slots }) {
-    return () => h('div', slots.default?.())
-  },
-})
-
-const NButtonStub = defineComponent({
-  props: ['title'],
-  setup(props, { slots }) {
-    return () => h('button', { title: props.title }, slots.default?.())
-  },
-})
-
-const NEmptyStub = defineComponent({
-  props: ['description'],
-  setup(props) {
-    return () => h('div', String(props.description || ''))
-  },
-})
-
-const NTreeStub = defineComponent({
-  props: ['data', 'renderLabel'],
-  setup(props) {
-    return () => h('div', (props.data || []).map((option: any) =>
-      h('div', { class: 'tree-node' }, [props.renderLabel({ option })]),
-    ))
-  },
-})
-
 function mountFileList() {
   return mount(FileList, {
     global: {
-      stubs: {
-        NSpin: NSpinStub,
-        NButton: NButtonStub,
-        NEmpty: NEmptyStub,
-      },
+      plugins: [ArcoVue],
     },
   })
 }
@@ -105,9 +66,7 @@ describe('workspace long names', () => {
 
     const wrapper = mount(FileTree, {
       global: {
-        stubs: {
-          NTree: NTreeStub,
-        },
+        plugins: [ArcoVue],
       },
     })
     await vi.waitFor(() => {