智教助手平台：完整初始化

- 前端：Vue3 + TS + Element Plus，24 个页面路由（课件/组题/教案/动画/思维导图/作文批改/命题/课堂/资源/社区等）
- 后端：FastAPI + SQLAlchemy + SQLite，17 个路由模块，AI 服务层含降级模板
- AI：glm-5.x 推理模型已禁用思维链，确保输出真实内容
- 修复：ai_service 两处请求体注入 enable_thinking/thinking disabled
- 测试账号：13900999999 / test1234

backend/models/exercise.py

@@ -0,0 +1,44 @@
+from sqlalchemy import Column, Integer, String, Text, DateTime, JSON, ForeignKey, Enum as SAEnum
+from sqlalchemy.orm import relationship
+from sqlalchemy.sql import func
+from database import Base
+
+
+class Exercise(Base):
+    __tablename__ = "exercises"
+
+    id = Column(Integer, primary_key=True, index=True)
+    user_id = Column(Integer, ForeignKey("users.id"), nullable=False)
+    title = Column(String(200), nullable=False)
+    exercise_type = Column(
+        SAEnum(
+            "game_snake", "game_match", "game_adventure",
+            "choice", "fill_blank", "true_false", "drag_sort", "matching",
+            name="exercise_type",
+        ),
+        default="choice",
+    )
+    subject = Column(String(50), default="")
+    knowledge_points = Column(JSON, default=list)
+    questions = Column(JSON, default=list)
+    settings = Column(JSON, default=dict)
+    created_at = Column(DateTime, server_default=func.now())
+    updated_at = Column(DateTime, server_default=func.now(), onupdate=func.now())
+
+    author = relationship("User", back_populates="exercises")
+    attempts = relationship("ExerciseAttempt", back_populates="exercise", lazy="selectin")
+
+
+class ExerciseAttempt(Base):
+    __tablename__ = "exercise_attempts"
+
+    id = Column(Integer, primary_key=True, index=True)
+    exercise_id = Column(Integer, ForeignKey("exercises.id"), nullable=False)
+    student_name = Column(String(50), default="")
+    answers = Column(JSON, default=list)
+    score = Column(Integer, default=0)
+    total = Column(Integer, default=0)
+    duration = Column(Integer, default=0)
+    created_at = Column(DateTime, server_default=func.now())
+
+    exercise = relationship("Exercise", back_populates="attempts")