feat: 审核体系全面改造 — 多维度评分 + 卖点优先级 + AI 语义匹配 + 品牌方 AI 状态通知

后端:
- 审核结果拆分为 4 个独立维度 (法规合规/平台规则/品牌安全/Brief匹配度)
- 卖点优先级从 required:bool 改为三级 (core/recommended/reference)
- AI 语义匹配卖点覆盖 + AI 整体 Brief 匹配度分析
- BriefMatchDetail 评分详情 (覆盖率+亮点+问题点)
- min_selling_points 代理商可配置最少卖点数 + Alembic 迁移
- AI 语境复核过滤误报
- Brief AI 解析 + 规则 AI 解析
- AI 未配置/异常时通知品牌方
- 种子数据更新 (新格式审核结果+brief_match_detail)

前端:
- 三端审核页面展示四维度评分卡片
- 卖点编辑改为三级优先级选择器
- BriefMatchDetail 展示 (覆盖率进度条+亮点+问题)
- min_selling_points 配置 UI
- AI 配置页未配置时静默处理
- 文件预览/下载/签名 URL 优化

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

frontend/components/ui/FilePreview.tsx

@@ -16,6 +16,7 @@ import {
 } from 'lucide-react'
 import { Button } from './Button'
 import { Modal } from './Modal'
+import { api } from '@/lib/api'
 
 // 文件信息类型
 export interface FileInfo {
@@ -98,20 +99,29 @@ export function FileInfoCard({
 }) {
   const category = getFileCategory(file)
 
-  const handleDownload = () => {
+  const handleDownload = async () => {
     if (onDownload) {
       onDownload()
     } else {
-      // 默认下载行为
-      const link = document.createElement('a')
-      link.href = file.fileUrl
-      link.download = file.fileName
-      link.click()
+      try {
+        await api.downloadFile(file.fileUrl, file.fileName)
+      } catch {
+        // 回退到直接链接下载
+        const link = document.createElement('a')
+        link.href = file.fileUrl
+        link.download = file.fileName
+        link.click()
+      }
     }
   }
 
-  const handleOpenInNewTab = () => {
-    window.open(file.fileUrl, '_blank')
+  const handleOpenInNewTab = async () => {
+    try {
+      const blobUrl = await api.getPreviewUrl(file.fileUrl)
+      window.open(blobUrl, '_blank')
+    } catch {
+      window.open(file.fileUrl, '_blank')
+    }
   }
 
   return (
@@ -300,15 +310,26 @@ export function DocumentPlaceholder({
           该文件格式暂不支持在线预览
         </p>
         <div className="flex gap-2 justify-center">
-          <Button variant="secondary" onClick={() => window.open(file.fileUrl, '_blank')}>
+          <Button variant="secondary" onClick={async () => {
+            try {
+              const blobUrl = await api.getPreviewUrl(file.fileUrl)
+              window.open(blobUrl, '_blank')
+            } catch {
+              window.open(file.fileUrl, '_blank')
+            }
+          }}>
             <ExternalLink size={16} />
             在新标签页打开
           </Button>
-          <Button onClick={() => {
-            const link = document.createElement('a')
-            link.href = file.fileUrl
-            link.download = file.fileName
-            link.click()
+          <Button onClick={async () => {
+            try {
+              await api.downloadFile(file.fileUrl, file.fileName)
+            } catch {
+              const link = document.createElement('a')
+              link.href = file.fileUrl
+              link.download = file.fileName
+              link.click()
+            }
           }}>
             <Download size={16} />
             下载文件
@@ -380,15 +401,26 @@ export function FilePreviewModal({
             )}
           </div>
           <div className="flex gap-2">
-            <Button variant="secondary" onClick={() => window.open(file.fileUrl, '_blank')}>
+            <Button variant="secondary" onClick={async () => {
+              try {
+                const blobUrl = await api.getPreviewUrl(file.fileUrl)
+                window.open(blobUrl, '_blank')
+              } catch {
+                window.open(file.fileUrl, '_blank')
+              }
+            }}>
               <ExternalLink size={16} />
               新标签页打开
             </Button>
-            <Button onClick={() => {
-              const link = document.createElement('a')
-              link.href = file.fileUrl
-              link.download = file.fileName
-              link.click()
+            <Button onClick={async () => {
+              try {
+                await api.downloadFile(file.fileUrl, file.fileName)
+              } catch {
+                const link = document.createElement('a')
+                link.href = file.fileUrl
+                link.download = file.fileName
+                link.click()
+              }
             }}>
               <Download size={16} />
               下载