Replace bytes.Replace with gjson.GetBytes+sjson.SetBytes in passthrough
mode to correctly handle JSON whitespace variations and avoid silently
sending empty body on read errors. Also add log search count limit to
prevent slow COUNT queries on large log tables.

- 注释侧边栏"聊天"子菜单，保留"操练场"
- 隐藏个人设置中的账户管理模块
- 隐藏其他设置中的价格设置和隐私设置Tab

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>