feat: show skills in status and sidebar

[connorads]

Adds skills list to the status page and sidebar.

Previously, I believe there was no way to see which skills were loaded in a session. Users had to explicitly ask the agent about loaded skills and hope for an accurate response.

Demos

Multiple skills

Shown in status and sidebar

Single skill

Doesn't show as collapsible sidebar ▶︎

No skills

Implementation considerations

I'm not precious about any of this just thought I'd mention it in case people want to change it.

• Uses green dot indicator (matching MCP) to show skills are active
  • Note: Currently I believe there's no deactivated state for skills, but the indicator maintains visual consistency with MCP and leaves room for future state management
• Skills are ordered alphabetically in the sidebar (same as MCP servers)
• When collapsed, the Skills section doesn't show a count (unlike MCP's "4 active")
  • Rationale: Skills don't have active/inactive states like MCP servers, so showing a count felt unnecessary. Skills are either loaded or not shown at all. And all the other sections don't have a count.
• Location/source information is not displayed
  • Consistent with MCP servers which I believe also don't show their source in status or sidebar