test: PR#27新增单元测试和e2e测试

后端: auto_translate/title_case 14个测试
前端: EDITOR_ONLY_TAGS、drop单复数、已下架过滤 11个测试
E2E: en_name title case、删除用户转移配方、管理配方登录引导

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

frontend/src/__tests__/pr27Features.test.js

@@ -0,0 +1,86 @@
+import { describe, it, expect } from 'vitest'
+
+// ---------------------------------------------------------------------------
+// EDITOR_ONLY_TAGS includes '已下架'
+// ---------------------------------------------------------------------------
+describe('EDITOR_ONLY_TAGS', () => {
+  it('includes 已审核', async () => {
+    const { EDITOR_ONLY_TAGS } = await import('../stores/recipes')
+    expect(EDITOR_ONLY_TAGS).toContain('已审核')
+  })
+
+  it('includes 已下架', async () => {
+    const { EDITOR_ONLY_TAGS } = await import('../stores/recipes')
+    expect(EDITOR_ONLY_TAGS).toContain('已下架')
+  })
+
+  it('is an array with at least 2 entries', async () => {
+    const { EDITOR_ONLY_TAGS } = await import('../stores/recipes')
+    expect(Array.isArray(EDITOR_ONLY_TAGS)).toBe(true)
+    expect(EDITOR_ONLY_TAGS.length).toBeGreaterThanOrEqual(2)
+  })
+})
+
+// ---------------------------------------------------------------------------
+// English drop/drops pluralization logic
+// ---------------------------------------------------------------------------
+describe('drop/drops pluralization', () => {
+  const pluralize = (n) => (n === 1 ? 'drop' : 'drops')
+
+  it('singular: 1 drop', () => {
+    expect(pluralize(1)).toBe('drop')
+  })
+
+  it('plural: 0 drops', () => {
+    expect(pluralize(0)).toBe('drops')
+  })
+
+  it('plural: 2 drops', () => {
+    expect(pluralize(2)).toBe('drops')
+  })
+
+  it('plural: 5 drops', () => {
+    expect(pluralize(5)).toBe('drops')
+  })
+})
+
+// ---------------------------------------------------------------------------
+// 已下架 tag filtering logic (pure function extraction)
+// ---------------------------------------------------------------------------
+describe('已下架 tag filtering', () => {
+  const recipes = [
+    { name: 'Active Recipe', tags: ['头疗'] },
+    { name: 'Delisted Recipe', tags: ['已下架'] },
+    { name: 'No Tags Recipe', tags: [] },
+    { name: 'Multi Tag', tags: ['热门', '已下架'] },
+    { name: 'Null Tags', tags: null },
+  ]
+
+  const filterDelisted = (list) =>
+    list.filter((r) => !r.tags || !r.tags.includes('已下架'))
+
+  it('removes recipes with 已下架 tag', () => {
+    const result = filterDelisted(recipes)
+    expect(result.map((r) => r.name)).not.toContain('Delisted Recipe')
+    expect(result.map((r) => r.name)).not.toContain('Multi Tag')
+  })
+
+  it('keeps recipes without 已下架 tag', () => {
+    const result = filterDelisted(recipes)
+    expect(result.map((r) => r.name)).toContain('Active Recipe')
+    expect(result.map((r) => r.name)).toContain('No Tags Recipe')
+  })
+
+  it('handles null tags gracefully', () => {
+    const result = filterDelisted(recipes)
+    expect(result.map((r) => r.name)).toContain('Null Tags')
+  })
+
+  it('returns empty array for all-delisted list', () => {
+    const all = [
+      { name: 'A', tags: ['已下架'] },
+      { name: 'B', tags: ['已下架', '其他'] },
+    ]
+    expect(filterDelisted(all)).toHaveLength(0)
+  })
+})