fix: 修复考试题目分数显示为小数的问题

- 使用 distributeScores 智能整数分配题目分数
- 格式化分数显示，避免显示长小数
- 总分100分，根据题目数量智能分配整数分数

例如：11道题 = [10,10,10,10,10,10,10,10,10,5,5] 而不是 [9.09...,9.09...]

frontend/src/views/exam/practice.vue

@@ -35,7 +35,7 @@
             <el-tag :type="getQuestionTypeTag(currentQuestion.type)">
               {{ getQuestionTypeText(currentQuestion.type) }}
             </el-tag>
-            <span class="question-score">{{ currentQuestion.score }} 分</span>
+            <span class="question-score">{{ formatScore(currentQuestion.score) }} 分</span>
           </div>
           
           <div class="question-content">
@@ -235,6 +235,7 @@ import { courseApi } from '@/api/course'
 import { generateExam, judgeAnswer, recordMistake, getMistakes, updateRoundScore, type MistakeRecordItem } from '@/api/exam'
 import { marked } from 'marked'
 import DOMPurify from 'dompurify'
+import { distributeScores, formatScore } from '@/utils/scoreFormatter'
 
 // 路由相关
 const route = useRoute()
@@ -358,6 +359,10 @@ const clearAnswer = () => {
  * 数据格式转换：Dify格式转前端格式
  */
 const transformDifyQuestions = (difyQuestions: any[]): any[] => {
+  // 使用智能分数分配，避免小数（总分100分）
+  const totalScore = 100
+  const scores = distributeScores(totalScore, difyQuestions.length)
+  
   return difyQuestions.map((q, index) => {
     const typeMap: Record<string, string> = {
       'single_choice': 'single',
@@ -371,7 +376,7 @@ const transformDifyQuestions = (difyQuestions: any[]): any[] => {
       id: index + 1,
       type: typeMap[q.type] || q.type,
       title: q.topic?.title || q.topic || '',
-      score: 10 / difyQuestions.length,  // 平均分配分值,总分10分
+      score: scores[index],  // 使用智能整数分配
       explanation: q.analysis || '',
       knowledge_point_id: q.knowledge_point_id ? parseInt(q.knowledge_point_id) : null
     }