feat: 完成管理员密码登录修复和项目清理

- 修复BCryptPasswordEncoder密码验证问题
- 实现密码设置提示弹窗功能（仅对无密码用户显示一次）
- 优化修改密码逻辑和验证流程
- 更新Welcome页面背景样式
- 清理临时SQL文件和测试代码
- 移动数据库备份文件到database/backups目录
- 删除不必要的MD文档和临时文件

demo/deploy_baota/frontend/static/payments-de89cd9e.js

@@ -0,0 +1 @@
+import{e}from"./index-467ea2ad.js";const a=t=>e.get("/payments",{params:t}),n=t=>e.get(`/payments/${t}`),r=t=>e.post("/payments/create",t),o=t=>e.post("/payments/create-test",t),p=t=>e.post(`/payments/${t}/test-complete`),c=t=>e.post("/payments/alipay/create",t),m=()=>e.get("/payments/subscription/info");export{r as a,c as b,o as c,n as d,m as e,a as g,p as t};