refactor: 清理无用模块、修复前后端对齐、添加注册页面

- 删除后端 risk_exceptions 模块（API/Model/Schema/迁移/测试）
- 删除后端 metrics 模块（API/测试）
- 删除后端 ManualTask 模型和相关 Schema
- 修复搜索接口响应缺少 total 字段的问题
- 统一 Platform 枚举（前端去掉后端不支持的 weibo/wechat）
- 新增前端注册页面 /register，登录页添加注册链接

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

frontend/hooks/useReview.ts

@@ -5,7 +5,7 @@ import { api } from '@/lib/api'
 import type {
   VideoReviewRequest,
   ReviewTask,
-  TaskStatus,
+  ReviewTaskStatus,
 } from '@/types/review'
 
 interface UseReviewOptions {
@@ -36,11 +36,11 @@ export function useReview(options: UseReviewOptions = {}) {
     try {
       const response = await api.submitVideoReview(data)
       setTask({
-        reviewId: response.reviewId,
+        review_id: response.review_id,
         status: response.status,
-        createdAt: new Date().toISOString(),
+        created_at: new Date().toISOString(),
       })
-      return response.reviewId
+      return response.review_id
     } catch (err) {
       const error = err instanceof Error ? err : new Error('提交失败')
       setError(error)
@@ -59,11 +59,11 @@ export function useReview(options: UseReviewOptions = {}) {
       const progress = await api.getReviewProgress(reviewId)
       setTask((prev) => ({
         ...prev,
-        reviewId: progress.reviewId,
+        review_id: progress.review_id,
         status: progress.status,
         progress: progress.progress,
-        currentStep: progress.currentStep,
-        createdAt: prev?.createdAt || new Date().toISOString(),
+        current_step: progress.current_step,
+        created_at: prev?.created_at || new Date().toISOString(),
       }))
       return progress
     } catch (err) {
@@ -80,14 +80,14 @@ export function useReview(options: UseReviewOptions = {}) {
     try {
       const result = await api.getReviewResult(reviewId)
       const updatedTask: ReviewTask = {
-        reviewId: result.reviewId,
+        review_id: result.review_id,
         status: result.status,
         score: result.score,
         summary: result.summary,
         violations: result.violations,
-        softWarnings: result.softWarnings,
-        createdAt: task?.createdAt || new Date().toISOString(),
-        completedAt: new Date().toISOString(),
+        soft_warnings: result.soft_warnings,
+        created_at: task?.created_at || new Date().toISOString(),
+        completed_at: new Date().toISOString(),
       }
       setTask(updatedTask)
       return updatedTask
@@ -96,7 +96,7 @@ export function useReview(options: UseReviewOptions = {}) {
       setError(error)
       throw error
     }
-  }, [task?.createdAt])
+  }, [task?.created_at])
 
   /**
    * 清除轮询定时器
@@ -203,13 +203,13 @@ export function useReviewResult(reviewId: string | null) {
       try {
         const result = await api.getReviewResult(reviewId)
         setTask({
-          reviewId: result.reviewId,
+          review_id: result.review_id,
           status: result.status,
           score: result.score,
           summary: result.summary,
           violations: result.violations,
-          softWarnings: result.softWarnings,
-          createdAt: new Date().toISOString(),
+          soft_warnings: result.soft_warnings,
+          created_at: new Date().toISOString(),
         })
       } catch (err) {
         setError(err instanceof Error ? err : new Error('查询失败'))