feat: 重新设计底部tab智图标为交叉斧剑

智(金)图标从大脑改为X型交叉斧和剑造型，象征谋略与力量。

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>