fix(contracts): 守卫收紧必填字段类型与对象形状；修复包级 test 脚本；补齐守卫测试与 REQUIRED 类型锁

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

packages/contracts/test/universal-row.test.ts

@@ -25,3 +25,33 @@ describe('UniversalRow 契约', () => {
     expect(isUniversalRow(bad)).toBe(false)
   })
 })
+
+const REQUIRED_KEYS = [
+  'sourceType', 'sourceId', 'status', 'locale',
+  'taxonomyRefs', 'attachmentRefs', 'seo', 'knownFields', 'extras', 'rawLocation',
+] as const
+
+describe('UniversalRow 守卫拒绝路径', () => {
+  it.each(REQUIRED_KEYS)('缺必填字段 %s 拒绝', (key) => {
+    const clone: Record<string, unknown> = { ...valid }
+    delete clone[key]
+    expect(isUniversalRow(clone)).toBe(false)
+  })
+
+  it('非对象输入拒绝（null / number）', () => {
+    expect(isUniversalRow(null)).toBe(false)
+    expect(isUniversalRow(42)).toBe(false)
+  })
+
+  it('taxonomyRefs 非数组拒绝', () => {
+    expect(isUniversalRow({ ...valid, taxonomyRefs: 'oops' })).toBe(false)
+  })
+
+  it('必填字符串字段非字符串拒绝（sourceId 数字）', () => {
+    expect(isUniversalRow({ ...valid, sourceId: 101 })).toBe(false)
+  })
+
+  it('seo 为数组拒绝（数组伪装对象）', () => {
+    expect(isUniversalRow({ ...valid, seo: [] })).toBe(false)
+  })
+})