feat(db): add grade_record_answers migration and update schema

- Add migration 0010 for grade_record_answers table

- Update shared DB schema with new table definitions

src/shared/db/schema.ts

@@ -159,7 +159,7 @@ export const knowledgePointPrerequisites = mysqlTable("knowledge_point_prerequis
   prerequisiteKpId: varchar("prerequisite_kp_id", { length: 128 }).notNull(),
   createdAt: timestamp("created_at").defaultNow().notNull(),
 }, (table) => ({
-  kpPairPk: primaryKey({ columns: [table.knowledgePointId, table.prerequisiteKpId] }),
+  kpPairPk: primaryKey({ columns: [table.knowledgePointId, table.prerequisiteKpId], name: "kp_prereq_pk" }),
   kpIdx: index("kp_prereq_kp_idx").on(table.knowledgePointId),
   prereqIdx: index("kp_prereq_prereq_idx").on(table.prerequisiteKpId),
   kpFk: foreignKey({
@@ -701,6 +701,8 @@ export const homeworkAnswers = mysqlTable("homework_answers", {
   }),
 }));
 
+export const aiProviderVisibilityEnum = mysqlEnum("visibility", ["public", "private"]);
+
 export const aiProviders = mysqlTable("ai_providers", {
   id: id("id").primaryKey(),
   provider: mysqlEnum("provider", ["zhipu", "openai", "gemini", "custom"]).notNull(),
@@ -709,6 +711,8 @@ export const aiProviders = mysqlTable("ai_providers", {
   apiKeyEncrypted: text("api_key_encrypted").notNull(),
   apiKeyLast4: varchar("api_key_last4", { length: 4 }),
   isDefault: boolean("is_default").default(false).notNull(),
+  // V3: 可见性 — public 由管理员发布，全员可用；private 仅创建者可见
+  visibility: aiProviderVisibilityEnum.default("private").notNull(),
   createdBy: varchar("created_by", { length: 128 }),
   updatedBy: varchar("updated_by", { length: 128 }),
   createdAt: timestamp("created_at").defaultNow().notNull(),
@@ -716,6 +720,8 @@ export const aiProviders = mysqlTable("ai_providers", {
 }, (table) => ({
   providerIdx: index("ai_provider_idx").on(table.provider),
   defaultIdx: index("ai_provider_default_idx").on(table.isDefault),
+  visibilityIdx: index("ai_provider_visibility_idx").on(table.visibility),
+  createdByIdx: index("ai_provider_created_by_idx").on(table.createdBy),
 }));
 
 // --- 8. Announcements ---
@@ -885,6 +891,32 @@ export const gradeRecords = mysqlTable("grade_records", {
   }).onDelete("cascade"),
 }));
 
+// --- 11.1 Grade Record Answers (成绩每题得分) ---
+
+export const gradeRecordAnswers = mysqlTable("grade_record_answers", {
+  id: id("id").primaryKey(),
+  gradeRecordId: varchar("grade_record_id", { length: 128 }).notNull().references(() => gradeRecords.id, { onDelete: "cascade" }),
+  questionId: varchar("question_id", { length: 128 }).notNull().references(() => questions.id, { onDelete: "cascade" }),
+  score: decimal("score", { precision: 6, scale: 2 }).notNull(),
+  fullScore: decimal("full_score", { precision: 6, scale: 2 }).notNull(),
+  feedback: text("feedback"),
+  createdAt: timestamp("created_at").defaultNow().notNull(),
+  updatedAt: timestamp("updated_at").defaultNow().onUpdateNow().notNull(),
+}, (table) => ({
+  gradeRecordIdx: index("grade_record_answers_record_idx").on(table.gradeRecordId),
+  questionIdx: index("grade_record_answers_question_idx").on(table.questionId),
+  gradeRecordFk: foreignKey({
+    columns: [table.gradeRecordId],
+    foreignColumns: [gradeRecords.id],
+    name: "gra_gr_fk",
+  }).onDelete("cascade"),
+  questionFk: foreignKey({
+    columns: [table.questionId],
+    foreignColumns: [questions.id],
+    name: "gra_q_fk",
+  }).onDelete("cascade"),
+}));
+
 // --- 12. File Attachments (文件附件) ---
 
 export const fileAttachments = mysqlTable("file_attachments", {
@@ -1540,3 +1572,100 @@ export const gradeDrafts = mysqlTable("grade_drafts", {
   ),
   userUpdatedIdx: index("gd_user_updated_idx").on(table.userId, table.updatedAt),
 }));
+
+// --- 28. Adaptive Practice (专项练习闭环) ---
+
+/**
+ * 专项练习类型。
+ * - error_variant: 错题变式练习（从错题本发起，生成变式题）
+ * - knowledge_point: 知识点专项练习（按知识点抽题）
+ * - weak_chapter: 薄弱章节练习（按掌握度自动推荐）
+ * - ai_recommended: AI 推荐练习（AI 根据学情综合推荐）
+ */
+export const practiceTypeEnum = mysqlEnum("practice_type", [
+  "error_variant",
+  "knowledge_point",
+  "weak_chapter",
+  "ai_recommended",
+]);
+
+export const practiceStatusEnum = mysqlEnum("practice_status", [
+  "in_progress",
+  "completed",
+  "abandoned",
+]);
+
+export const practiceAnswerStatusEnum = mysqlEnum("practice_answer_status", [
+  "pending",
+  "answered",
+  "skipped",
+]);
+
+/**
+ * 专项练习会话 - 学生发起的一次专项练习。
+ *
+ * 记录练习类型、来源元数据（知识点/错题/章节）、状态和统计。
+ * 练习题目存储在 practiceAnswers 表中。
+ */
+export const practiceSessions = mysqlTable("practice_sessions", {
+  id: id("id").primaryKey(),
+  studentId: varchar("student_id", { length: 128 }).notNull().references(() => users.id, { onDelete: "cascade" }),
+  subjectId: varchar("subject_id", { length: 128 }),
+
+  practiceType: practiceTypeEnum.notNull(),
+  /** 来源元数据：{ knowledgePointIds?, errorBookItemIds?, chapterId?, difficulty?, sourceQuestionId? } */
+  sourceMeta: json("source_meta"),
+
+  status: practiceStatusEnum.default("in_progress").notNull(),
+
+  totalQuestions: int("total_questions").default(0).notNull(),
+  answeredQuestions: int("answered_questions").default(0).notNull(),
+  correctCount: int("correct_count").default(0).notNull(),
+
+  startedAt: timestamp("started_at", { mode: "date" }).defaultNow().notNull(),
+  completedAt: timestamp("completed_at", { mode: "date" }),
+
+  createdAt: timestamp("created_at").defaultNow().notNull(),
+  updatedAt: timestamp("updated_at").defaultNow().onUpdateNow().notNull(),
+}, (table) => ({
+  studentIdx: index("ps_student_idx").on(table.studentId),
+  studentStatusIdx: index("ps_student_status_idx").on(table.studentId, table.status),
+  subjectIdx: index("ps_subject_idx").on(table.subjectId),
+}));
+
+/**
+ * 专项练习答题记录 - 会话中每道题的作答情况。
+ *
+ * 支持两种题目来源：
+ * 1. 题库中的题目（questionId 指向 questions 表）
+ * 2. AI 生成的变式题（variantContent 存储 JSON 内容，questionId 指向原题）
+ */
+export const practiceAnswers = mysqlTable("practice_answers", {
+  id: id("id").primaryKey(),
+  sessionId: varchar("session_id", { length: 128 }).notNull().references(() => practiceSessions.id, { onDelete: "cascade" }),
+  studentId: varchar("student_id", { length: 128 }).notNull().references(() => users.id, { onDelete: "cascade" }),
+
+  questionId: varchar("question_id", { length: 128 }).notNull().references(() => questions.id),
+  /** 变式题内容（AI 生成的变式题，未入库时存储在此字段） */
+  variantContent: json("variant_content"),
+  /** 是否为变式题 */
+  isVariant: boolean("is_variant").default(false).notNull(),
+
+  orderIndex: int("order_index").notNull(),
+  status: practiceAnswerStatusEnum.default("pending").notNull(),
+
+  studentAnswer: json("student_answer"),
+  isCorrect: boolean("is_correct"),
+  score: int("score"),
+  maxScore: int("max_score").default(1).notNull(),
+
+  answeredAt: timestamp("answered_at", { mode: "date" }),
+
+  createdAt: timestamp("created_at").defaultNow().notNull(),
+  updatedAt: timestamp("updated_at").defaultNow().onUpdateNow().notNull(),
+}, (table) => ({
+  sessionIdx: index("pa_session_idx").on(table.sessionId),
+  studentIdx: index("pa_student_idx").on(table.studentId),
+  questionIdx: index("pa_question_idx").on(table.questionId),
+  sessionOrderIdx: index("pa_session_order_idx").on(table.sessionId, table.orderIndex),
+}));