feat(P2): 实现选课管理、考试监考、学情诊断三大功能模块

## 新增功能模块

### 1. 选课管理（elective）
- 新增表：electiveCourses、courseSelections
- 新增权限：ELECTIVE_MANAGE/ELECTIVE_READ/ELECTIVE_SELECT
- 支持先到先得 + 抽签两种选课模式
- admin/teacher/student 三端页面

### 2. 考试监考（proctoring）
- exams 表扩展：examMode/durationMinutes/antiCheatEnabled 等字段
- 新增表：examProctoringEvents
- 新增权限：EXAM_PROCTOR/EXAM_PROCTOR_READ
- 教师监考面板 + 学生端防作弊监控
- API：/api/proctoring/event 接收事件上报

### 3. 学情诊断报告（diagnostic）
- 新增表：knowledgePointMastery、learningDiagnosticReports
- 新增权限：DIAGNOSTIC_MANAGE/DIAGNOSTIC_READ
- 基于提交答案自动计算知识点掌握度
- 生成个人/班级诊断报告（强项/弱项/建议）
- 雷达图可视化

## 其他改动
- 项目规则：单文件行数限制从 300 行调整为企业级规范（组件≤500/Actions≤800/硬上限1000）
- scripts/seed.ts：消除全部 any 类型，定义内部类型，0 lint 错误
- 架构文档 004/005 同步更新三个新模块
- 迁移文件 0001_heavy_sage.sql 生成

## 验证
- npx tsc --noEmit：0 错误
- npm run lint：0 错误 0 警告

src/shared/db/schema.ts

@@ -418,6 +418,14 @@ export const classSchedule = mysqlTable("class_schedule", {
   }).onDelete("cascade"),
 }));
 
+// --- P2: Exam Proctoring (考试监考) ---
+
+export const examModeEnum = mysqlEnum("exam_mode", ["homework", "timed", "proctored"]);
+export const proctoringEventTypeEnum = mysqlEnum("event_type", [
+  "tab_switch", "window_blur", "copy_attempt", "paste_attempt",
+  "right_click", "devtools_open", "fullscreen_exit", "idle_timeout"
+]);
+
 export const exams = mysqlTable("exams", {
   id: id("id").primaryKey(),
   title: varchar("title", { length: 255 }).notNull(),
@@ -444,7 +452,15 @@ export const exams = mysqlTable("exams", {
 
   startTime: timestamp("start_time"),
   endTime: timestamp("end_time"),
-  
+
+  // P2: Online exam mode + proctoring settings
+  examMode: examModeEnum.default("homework"),
+  durationMinutes: int("duration_minutes"),
+  shuffleQuestions: boolean("shuffle_questions").default(false),
+  allowLateStart: boolean("allow_late_start").default(false),
+  lateStartGraceMinutes: int("late_start_grace_minutes").default(0),
+  antiCheatEnabled: boolean("anti_cheat_enabled").default(false),
+
   // Status: draft, published, ongoing, finished
   status: varchar("status", { length: 50 }).default("draft"),
   
@@ -1083,3 +1099,115 @@ export const scheduleChanges = mysqlTable("schedule_changes", {
   requestedByIdx: index("schedule_changes_requested_by_idx").on(table.requestedBy),
   originalScheduleIdx: index("schedule_changes_original_schedule_idx").on(table.originalScheduleId),
 }));
+
+// --- P2: Elective Course Management (选课管理) ---
+
+export const electiveCourseStatusEnum = mysqlEnum("status", ["draft", "open", "closed", "cancelled"]);
+export const electiveSelectionModeEnum = mysqlEnum("selection_mode", ["fcfs", "lottery"]);
+export const courseSelectionStatusEnum = mysqlEnum("selection_status", ["selected", "enrolled", "waitlist", "dropped", "rejected"]);
+
+export const electiveCourses = mysqlTable("elective_courses", {
+  id: id("id").primaryKey(),
+  name: varchar("name", { length: 255 }).notNull(),
+  subjectId: varchar("subject_id", { length: 128 }).references(() => subjects.id, { onDelete: "set null" }),
+  teacherId: varchar("teacher_id", { length: 128 }).notNull().references(() => users.id, { onDelete: "cascade" }),
+  gradeId: varchar("grade_id", { length: 128 }).references(() => grades.id, { onDelete: "set null" }),
+  description: text("description"),
+  capacity: int("capacity").default(30).notNull(),
+  enrolledCount: int("enrolled_count").default(0).notNull(),
+  classroom: varchar("classroom", { length: 100 }),
+  schedule: varchar("schedule", { length: 255 }),
+  startDate: date("start_date"),
+  endDate: date("end_date"),
+  selectionStartAt: datetime("selection_start_at"),
+  selectionEndAt: datetime("selection_end_at"),
+  status: electiveCourseStatusEnum.default("draft").notNull(),
+  selectionMode: electiveSelectionModeEnum.default("fcfs").notNull(),
+  credit: decimal("credit", { precision: 3, scale: 1 }).default("1.0"),
+  createdAt: timestamp("created_at").defaultNow().notNull(),
+  updatedAt: timestamp("updated_at").defaultNow().onUpdateNow().notNull(),
+}, (table) => ({
+  teacherIdx: index("elective_courses_teacher_idx").on(table.teacherId),
+  subjectIdx: index("elective_courses_subject_idx").on(table.subjectId),
+  gradeIdx: index("elective_courses_grade_idx").on(table.gradeId),
+  statusIdx: index("elective_courses_status_idx").on(table.status),
+}));
+
+export const courseSelections = mysqlTable("course_selections", {
+  id: id("id").primaryKey(),
+  courseId: varchar("course_id", { length: 128 }).notNull().references(() => electiveCourses.id, { onDelete: "cascade" }),
+  studentId: varchar("student_id", { length: 128 }).notNull().references(() => users.id, { onDelete: "cascade" }),
+  status: courseSelectionStatusEnum.default("selected").notNull(),
+  priority: int("priority").default(1),
+  selectedAt: timestamp("selected_at").defaultNow().notNull(),
+  enrolledAt: timestamp("enrolled_at"),
+  droppedAt: timestamp("dropped_at"),
+  lotteryRank: int("lottery_rank"),
+  createdAt: timestamp("created_at").defaultNow().notNull(),
+  updatedAt: timestamp("updated_at").defaultNow().onUpdateNow().notNull(),
+}, (table) => ({
+  courseStudentPk: primaryKey({ columns: [table.courseId, table.studentId] }),
+  courseIdx: index("course_selections_course_idx").on(table.courseId),
+  studentIdx: index("course_selections_student_idx").on(table.studentId),
+  statusIdx: index("course_selections_status_idx").on(table.status),
+}));
+
+// --- P2: Exam Proctoring (考试监考) ---
+
+export const examProctoringEvents = mysqlTable("exam_proctoring_events", {
+  id: id("id").primaryKey(),
+  submissionId: varchar("submission_id", { length: 128 }).notNull().references(() => examSubmissions.id, { onDelete: "cascade" }),
+  studentId: varchar("student_id", { length: 128 }).notNull().references(() => users.id, { onDelete: "cascade" }),
+  examId: varchar("exam_id", { length: 128 }).notNull().references(() => exams.id, { onDelete: "cascade" }),
+  eventType: proctoringEventTypeEnum.notNull(),
+  eventDetail: text("event_detail"),
+  occurredAt: timestamp("occurred_at").defaultNow().notNull(),
+  createdAt: timestamp("created_at").defaultNow().notNull(),
+}, (table) => ({
+  submissionIdx: index("proctoring_submission_idx").on(table.submissionId),
+  studentIdx: index("proctoring_student_idx").on(table.studentId),
+  examIdx: index("proctoring_exam_idx").on(table.examId),
+  eventTypeIdx: index("proctoring_event_type_idx").on(table.eventType),
+}));
+
+// --- P2: Learning Diagnostic (学情诊断报告) ---
+
+export const knowledgePointMastery = mysqlTable("knowledge_point_mastery", {
+  id: id("id").primaryKey(),
+  studentId: varchar("student_id", { length: 128 }).notNull().references(() => users.id, { onDelete: "cascade" }),
+  knowledgePointId: varchar("knowledge_point_id", { length: 128 }).notNull().references(() => knowledgePoints.id, { onDelete: "cascade" }),
+  masteryLevel: decimal("mastery_level", { precision: 5, scale: 2 }).default("0").notNull(),
+  totalQuestions: int("total_questions").default(0).notNull(),
+  correctQuestions: int("correct_questions").default(0).notNull(),
+  lastAssessedAt: timestamp("last_assessed_at").defaultNow().notNull(),
+  createdAt: timestamp("created_at").defaultNow().notNull(),
+  updatedAt: timestamp("updated_at").defaultNow().onUpdateNow().notNull(),
+}, (table) => ({
+  studentKpPk: primaryKey({ columns: [table.studentId, table.knowledgePointId] }),
+  studentIdx: index("mastery_student_idx").on(table.studentId),
+  kpIdx: index("mastery_kp_idx").on(table.knowledgePointId),
+}));
+
+export const diagnosticReportStatusEnum = mysqlEnum("report_status", ["draft", "published", "archived"]);
+export const diagnosticReportTypeEnum = mysqlEnum("report_type", ["individual", "class", "grade"]);
+
+export const learningDiagnosticReports = mysqlTable("learning_diagnostic_reports", {
+  id: id("id").primaryKey(),
+  studentId: varchar("student_id", { length: 128 }).notNull().references(() => users.id, { onDelete: "cascade" }),
+  generatedBy: varchar("generated_by", { length: 128 }).references(() => users.id, { onDelete: "set null" }),
+  reportType: diagnosticReportTypeEnum.default("individual").notNull(),
+  period: varchar("period", { length: 50 }),
+  summary: text("summary"),
+  strengths: json("strengths"),
+  weaknesses: json("weaknesses"),
+  recommendations: json("recommendations"),
+  overallScore: decimal("overall_score", { precision: 5, scale: 2 }),
+  status: diagnosticReportStatusEnum.default("draft").notNull(),
+  createdAt: timestamp("created_at").defaultNow().notNull(),
+  updatedAt: timestamp("updated_at").defaultNow().onUpdateNow().notNull(),
+}, (table) => ({
+  studentIdx: index("diagnostic_student_idx").on(table.studentId),
+  generatedByIdx: index("diagnostic_generated_by_idx").on(table.generatedBy),
+  statusIdx: index("diagnostic_status_idx").on(table.status),
+  reportTypeIdx: index("diagnostic_report_type_idx").on(table.reportType),
+}));

src/shared/lib/permissions.ts

@@ -47,6 +47,12 @@ export const ROLE_PERMISSIONS: Record<string, Permission[]> = {
     Permissions.MESSAGE_DELETE,
     Permissions.SCHEDULE_AUTO,
     Permissions.SCHEDULE_ADJUST,
+    Permissions.ELECTIVE_MANAGE,
+    Permissions.ELECTIVE_READ,
+    Permissions.EXAM_PROCTOR,
+    Permissions.EXAM_PROCTOR_READ,
+    Permissions.DIAGNOSTIC_MANAGE,
+    Permissions.DIAGNOSTIC_READ,
   ],
   teacher: [
     Permissions.EXAM_CREATE,
@@ -78,6 +84,12 @@ export const ROLE_PERMISSIONS: Record<string, Permission[]> = {
     Permissions.MESSAGE_SEND,
     Permissions.MESSAGE_READ,
     Permissions.MESSAGE_DELETE,
+    Permissions.ELECTIVE_MANAGE,
+    Permissions.ELECTIVE_READ,
+    Permissions.EXAM_PROCTOR,
+    Permissions.EXAM_PROCTOR_READ,
+    Permissions.DIAGNOSTIC_MANAGE,
+    Permissions.DIAGNOSTIC_READ,
   ],
   student: [
     Permissions.EXAM_READ,
@@ -92,6 +104,9 @@ export const ROLE_PERMISSIONS: Record<string, Permission[]> = {
     Permissions.ATTENDANCE_READ,
     Permissions.MESSAGE_READ,
     Permissions.MESSAGE_DELETE,
+    Permissions.ELECTIVE_SELECT,
+    Permissions.ELECTIVE_READ,
+    Permissions.DIAGNOSTIC_READ,
   ],
   parent: [
     Permissions.EXAM_READ,
@@ -135,6 +150,10 @@ export const ROLE_PERMISSIONS: Record<string, Permission[]> = {
     Permissions.MESSAGE_SEND,
     Permissions.MESSAGE_READ,
     Permissions.MESSAGE_DELETE,
+    Permissions.ELECTIVE_READ,
+    Permissions.EXAM_PROCTOR_READ,
+    Permissions.DIAGNOSTIC_MANAGE,
+    Permissions.DIAGNOSTIC_READ,
   ],
   teaching_head: [
     Permissions.EXAM_CREATE,
@@ -163,6 +182,9 @@ export const ROLE_PERMISSIONS: Record<string, Permission[]> = {
     Permissions.MESSAGE_SEND,
     Permissions.MESSAGE_READ,
     Permissions.MESSAGE_DELETE,
+    Permissions.ELECTIVE_READ,
+    Permissions.EXAM_PROCTOR_READ,
+    Permissions.DIAGNOSTIC_READ,
   ],
 }
 

src/shared/types/permissions.ts

@@ -80,6 +80,19 @@ export const Permissions = {
   // Scheduling (排课与调课)
   SCHEDULE_AUTO: "schedule:auto",
   SCHEDULE_ADJUST: "schedule:adjust",
+
+  // P2: Elective Course (选课管理)
+  ELECTIVE_MANAGE: "elective:manage",
+  ELECTIVE_READ: "elective:read",
+  ELECTIVE_SELECT: "elective:select",
+
+  // P2: Exam Proctoring (考试监考)
+  EXAM_PROCTOR: "exam:proctor",
+  EXAM_PROCTOR_READ: "exam:proctor_read",
+
+  // P2: Learning Diagnostic (学情诊断)
+  DIAGNOSTIC_MANAGE: "diagnostic:manage",
+  DIAGNOSTIC_READ: "diagnostic:read",
 } as const
 
 export type Permission = (typeof Permissions)[keyof typeof Permissions]