feat: 风险分定时衰减 + 密码提示修复 + 浏览器池API + next回跳

1. 风险分衰减定时任务:
   - services/scheduler.py: 每天 CST 04:00 自动执行 decay_scores()
   - 支持 RISK_SCORE_DECAY_TIME_CST 环境变量覆盖

2. 密码长度提示统一为8位:
   - app-frontend/src/pages/RegisterPage.vue
   - app-frontend/src/layouts/AppLayout.vue
   - admin-frontend/src/pages/SettingsPage.vue
   - templates/register.html

3. 浏览器池统计API:
   - GET /yuyx/api/browser_pool/stats
   - 返回 worker 状态、队列等待数等信息
   - browser_pool_worker.py: 增强 get_stats() 方法

4. 登录后支持 next 参数回跳:
   - app-frontend/src/pages/LoginPage.vue: 检查 ?next= 参数
   - 仅允许站内路径（防止开放重定向）

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

static/admin/assets/users-BNPg4OEj.js

@@ -0,0 +1 @@
+import{P as t}from"./index-Dx-1XhY8.js";async function n(){const{data:s}=await t.get("/users");return s}async function o(s){const{data:a}=await t.post(`/users/${s}/approve`);return a}async function c(s){const{data:a}=await t.post(`/users/${s}/reject`);return a}async function i(s){const{data:a}=await t.delete(`/users/${s}`);return a}async function u(s,a){const{data:e}=await t.post(`/users/${s}/vip`,{days:a});return e}async function p(s){const{data:a}=await t.delete(`/users/${s}/vip`);return a}async function d(s,a){const{data:e}=await t.post(`/users/${s}/reset_password`,{new_password:a});return e}export{o as a,p as b,d as c,i as d,n as f,c as r,u as s};