/mcp command should work in context of /agent selected

### Describe the feature or problem you'd like to solve

now the /mcp awarness is global and only for main agent

### Proposed solution

when I've got two agents main and additional , and switching an agent by /agent command then type /mcp I see only global mcp servers , same as for main agent, so I cannot managed or even see them when I am on additional agent

it's expected to be presented within agent scope - telling a user which mcp server belongs to which agent , or see only from currently selected agents

### Example prompts or workflows

_No response_

### Additional context

GitHub Copilot CLI 1.0.34.