[feature] make agent hub like github

[hsluoyz]

see hub page: https://try.openagentai.org/hub

then go to agent page: https://try.openagentai.org/agents/admin/store-built-in

this page should be like github's repo page like: https://github.com/the-open-agent/openagent

we should have similar section like github, maybe not finished in one PR