feat: 后端 CRUD 完成（episodes + yearly_targets + users 管理 API）

backend/app/main.py

@@ -7,6 +7,9 @@ from starlette.middleware.cors import CORSMiddleware
 from starlette.middleware.sessions import SessionMiddleware
 
 from app.api.auth import router as auth_router
+from app.api.episodes import router as episodes_router
+from app.api.users import router as users_router
+from app.api.yearly_targets import router as yearly_targets_router
 from app.core.config import settings
 
 app = FastAPI(title="军事科技工作台", version="0.1.0")
@@ -33,4 +36,7 @@ app.add_middleware(
 )
 
 # ---- 注册路由 ----
-app.include_router(auth_router)
+app.include_router(auth_router)
+app.include_router(episodes_router)
+app.include_router(yearly_targets_router)
+app.include_router(users_router)