fix(dev): bind frontend to 127.0.0.1:8080 and avoid EACCES\nfix(backend): bind server to 127.0.0.1:8081, add permissive CORS whitelist\nfix(auth): login form UX remove default username, clarify placeholder, add test account autofill\nchore(api): set frontend API_BASE_URL to 127.0.0.1:8081\nrefactor(assignments): lifecycle/state logic and archive endpoint\nfeat(analytics): add exam stats endpoint and client method\nchore(lint): add eslint configs

UI_DTO.ts

@@ -246,8 +246,12 @@ export interface ExamDto {
     totalScore: number;
     duration: number;  // 建议时长（分钟）
     questionCount: number;  // 总题数
+    usageCount?: number;
     status: 'Draft' | 'Published';
     createdAt: string;
+    creatorName?: string;
+    isMyExam?: boolean;
+    examType?: string;
 }
 
 /**
@@ -273,6 +277,9 @@ export interface ExamNodeDto {
 
     // === 递归子节点 ===
     children?: ExamNodeDto[];  // 子节点（支持无限嵌套）
+
+    // === 学生作答（用于恢复进度） ===
+    studentAnswer?: any;
 }
 
 /**
@@ -304,24 +311,67 @@ export interface ExamStatsDto {
 // 6. Assignment / 作业
 // ============================================================
 
+export interface AssignmentAnalysisDto {
+    overview: {
+        title: string;
+        examTitle: string;
+        totalStudents: number;
+        submittedCount: number;
+        averageScore: number;
+        maxScore: number;
+        minScore: number;
+    };
+    questions: {
+        id: string;
+        title: string;
+        questionId: string | null;
+        score: number;
+        totalAnswers: number;
+        errorCount: number;
+        errorRate: number;
+        correctAnswer: string;
+        knowledgePoints: string[];
+        wrongSubmissions: {
+            studentName: string;
+            studentAnswer: string;
+        }[];
+    }[];
+    knowledgePoints: {
+        name: string;
+        errorRate: number;
+    }[];
+}
+
 export interface AssignmentTeacherViewDto {
     id: string;
     title: string;
+    examTitle: string;
+    subjectName?: string;
+    examType?: string;
     className: string;
+    gradeName: string;
     submittedCount: number;
     totalCount: number;
-    status: 'Active' | 'Ended' | 'Scheduled';
+    status: string; // 'Active' | 'Closed' | 'Ended'
+    hasPendingGrading?: boolean;
     dueDate: string;
-    examTitle: string;
+    createdAt: string;
 }
 
 export interface AssignmentStudentViewDto {
     id: string;
     title: string;
     examTitle: string;
+    subjectName?: string;
+    teacherName?: string;
+    duration?: number;
+    questionCount?: number;
+    totalScore?: number;
+    className?: string;
     endTime: string;
-    status: 'Pending' | 'Graded' | 'Submitted';
+    status: 'Pending' | 'InProgress' | 'Submitted' | 'Grading' | 'Completed';
     score?: number;
+    isSubmitted?: boolean; // Helper flag to distinguish between 'Grading' (expired but not submitted) vs (submitted)
 }
 
 // ============================================================