学生资料设置、头像与自动备份恢复。

首页卡片支持修改/删除；详情页设置 Tab 可维护学校、年级与头像；系统设置新增数据备份下载与恢复；备份默认存 /root/grade-archive-backups，详见 docs/BACKUP.md。

Co-authored-by: Cursor <cursoragent@cursor.com>

backend/app/main.py

@@ -1,5 +1,8 @@
 from contextlib import asynccontextmanager
 from pathlib import Path
+import logging
+import threading
+import time
 
 from fastapi import FastAPI, HTTPException
 from fastapi.middleware.cors import CORSMiddleware
@@ -8,7 +11,8 @@ from fastapi.staticfiles import StaticFiles
 
 from app.core.config import settings
 from app.core.database import Base, SessionLocal, engine
-from app.routers import admin, auth, compositions, exams, export, settings as settings_router, students, subjects, wrong_questions
+from app.routers import admin, auth, backups, compositions, exams, export, settings as settings_router, students, subjects, wrong_questions
+from app.services import backup as backup_service
 from app.services import ocr as ocr_service
 from app.services.migrate import run_migrations
 from app.services.seed import seed_admin_and_settings, seed_subjects
@@ -24,9 +28,21 @@ def resolve_frontend_dist() -> Path | None:
     return None
 
 
+def _auto_backup_loop() -> None:
+    interval = max(settings.AUTO_BACKUP_INTERVAL_HOURS, 1) * 3600
+    time.sleep(300)
+    while True:
+        try:
+            backup_service.create_backup()
+        except Exception:
+            logging.getLogger(__name__).exception("自动备份失败")
+        time.sleep(interval)
+
+
 @asynccontextmanager
 async def lifespan(app: FastAPI):
     Path(settings.UPLOAD_DIR).mkdir(parents=True, exist_ok=True)
+    Path(settings.BACKUP_DIR).mkdir(parents=True, exist_ok=True)
     Base.metadata.create_all(bind=engine)
     run_migrations()
     db = SessionLocal()
@@ -36,6 +52,8 @@ async def lifespan(app: FastAPI):
     finally:
         db.close()
     ocr_service.warmup_ocr_engine()
+    if settings.AUTO_BACKUP_INTERVAL_HOURS > 0:
+        threading.Thread(target=_auto_backup_loop, daemon=True).start()
     yield
 
 
@@ -53,6 +71,7 @@ app.add_middleware(
 app.include_router(auth.router, prefix="/api")
 app.include_router(settings_router.router, prefix="/api")
 app.include_router(admin.router, prefix="/api")
+app.include_router(backups.router, prefix="/api")
 app.include_router(students.router, prefix="/api")
 app.include_router(subjects.router, prefix="/api")
 app.include_router(exams.router, prefix="/api")