feat: API Key 静默认证 + 多邮箱支持

核心改动：
- V3 迁移: accounts 加 api_key/api_secret + account_emails 多邮箱关联表
- HMAC 验签改用 api_secret 替代密码哈希（改密码不影响集成）
- findByAnyEmail 支持主邮箱 + 关联邮箱查找
- AdminController: API Key 生成/重置 + 邮箱绑定/解绑/列表
- 前端 Users.vue: API Key 列 + 生成按钮 + Secret 复制弹窗
- 现有邮箱自动迁移到 account_emails 表

认证流程:
  旧: X-Email → account.email → passwordHash 作 HMAC key
  新: X-Email → account_emails ∪ account.email → api_secret 作 HMAC key

web/src/api/index.js

@@ -44,7 +44,8 @@ export default {
   },
   users: {
     list: () => api.get('/admin/accounts'),
-    setTrustLevel: (id, level) => api.post(`/admin/accounts/${id}/trust-level`, null, { params: { level } })
+    setTrustLevel: (id, level) => api.post(`/admin/accounts/${id}/trust-level`, null, { params: { level } }),
+    genApiKey: (id) => api.post(`/admin/accounts/${id}/api-key`)
   },
   health: () => api.get('/health', { baseURL: '' })
 }

web/src/views/Users.vue

@@ -3,37 +3,69 @@
     <h2>用户管理</h2>
     <el-card style="margin-top: 20px">
       <el-table :data="users" v-loading="loading" stripe>
-        <el-table-column prop="id" label="ID" width="80" />
-        <el-table-column prop="email" label="邮箱" />
-        <el-table-column prop="displayName" label="昵称" width="150" />
-        <el-table-column prop="trustLevel" label="信任等级" width="100">
+        <el-table-column prop="id" label="ID" width="60" />
+        <el-table-column prop="email" label="邮箱" min-width="180" />
+        <el-table-column prop="displayName" label="昵称" width="120" />
+        <el-table-column label="API Key" min-width="180">
+          <template #default="scope">
+            <span v-if="scope.row.apiKey" style="font-family:monospace;font-size:12px">{{ scope.row.apiKey }}</span>
+            <el-tag v-else size="small" type="info">未生成</el-tag>
+          </template>
+        </el-table-column>
+        <el-table-column prop="trustLevel" label="信任等级" width="90">
           <template #default="scope">
             <el-tag :type="trustLevelType(scope.row.trustLevel)">
               {{ trustLevelLabel(scope.row.trustLevel) }}
             </el-tag>
           </template>
         </el-table-column>
-        <el-table-column prop="isActive" label="状态" width="80">
+        <el-table-column prop="isActive" label="状态" width="70">
           <template #default="scope">
             <el-tag :type="scope.row.isActive ? 'success' : 'danger'">
               {{ scope.row.isActive ? '启用' : '禁用' }}
             </el-tag>
           </template>
         </el-table-column>
-        <el-table-column prop="createdAt" label="注册时间" width="180" />
-        <el-table-column label="操作" width="120">
+        <el-table-column prop="createdAt" label="注册时间" width="160" />
+        <el-table-column label="操作" width="200" fixed="right">
           <template #default="scope">
+            <el-button size="small" @click="handleGenKey(scope.row)">生成密钥</el-button>
             <el-button
               v-if="scope.row.trustLevel !== 'ADMIN'"
               size="small"
               @click="handleSetLevel(scope.row)"
             >设置等级</el-button>
-            <span v-else style="color:#999;font-size:12px">管理员</span>
           </template>
         </el-table-column>
       </el-table>
     </el-card>
 
+    <!-- API Key 弹窗 -->
+    <el-dialog v-model="keyDialogVisible" title="API Key" width="500px" :close-on-click-modal="false">
+      <el-alert type="warning" :closable="false" style="margin-bottom:16px">
+        Secret 仅在生成时显示一次，请立即复制保存！
+      </el-alert>
+      <el-form label-width="80px">
+        <el-form-item label="API Key">
+          <el-input v-model="keyResult.apiKey" readonly>
+            <template #append>
+              <el-button @click="copyText(keyResult.apiKey)">复制</el-button>
+            </template>
+          </el-input>
+        </el-form-item>
+        <el-form-item label="API Secret">
+          <el-input v-model="keyResult.apiSecret" readonly type="textarea" :rows="2">
+            <template #append>
+              <el-button @click="copyText(keyResult.apiSecret)">复制</el-button>
+            </template>
+          </el-input>
+        </el-form-item>
+      </el-form>
+      <template #footer>
+        <el-button @click="keyDialogVisible = false">关闭</el-button>
+      </template>
+    </el-dialog>
+
     <!-- 等级设置弹窗 -->
     <el-dialog v-model="dialogVisible" title="设置信任等级" width="400px">
       <el-form :model="levelForm">
@@ -63,6 +95,8 @@ const loading = ref(false)
 const dialogVisible = ref(false)
 const saving = ref(false)
 const levelForm = reactive({ id: null, email: '', level: '' })
+const keyDialogVisible = ref(false)
+const keyResult = reactive({ apiKey: '', apiSecret: '' })
 
 const trustLevelType = (level) => {
   const map = { MEMBER: '', TRUSTED: 'warning', ADMIN: 'danger' }
@@ -86,6 +120,22 @@ const fetchUsers = async () => {
   }
 }
 
+const handleGenKey = async (row) => {
+  try {
+    const res = await api.users.genApiKey(row.id)
+    keyResult.apiKey = res.data.apiKey
+    keyResult.apiSecret = res.data.apiSecret
+    keyDialogVisible.value = true
+    fetchUsers()
+  } catch (e) {
+    ElMessage.error(e.response?.data?.message || '生成失败')
+  }
+}
+
+const copyText = (text) => {
+  navigator.clipboard.writeText(text).then(() => ElMessage.success('已复制'))
+}
+
 const handleSetLevel = (row) => {
   levelForm.id = row.id
   levelForm.email = row.email