[FEATURE]:add skill white list for subagent

[2015chunhui]

Feature hasn't been suggested before.

• I have verified this feature I'm about to request hasn't been suggested before.

Describe the enhancement you want to request

I hope to add a configuration option for the sub-agent to set a whitelist of allowed skills. Currently, it only supports whether skill execution is allowed or not, but does not support setting an allowed skill list.

[github-actions]

This issue might be a duplicate of existing issues. Please check:

• [FEATURE]: Agent-scoped skill loading — only load skills declared by the active agent #19344: Requests agent-scoped skill loading — agents declaring a whitelist of skills they can use, which is very similar to this request for a skill whitelist for subagents.