[FEATURE]: Add parameter to not run any MCP server

[kud]

Feature hasn't been suggested before.

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

Describe the enhancement you want to request

It would be great to be able to pass a parameter to disable mcp servers while running a command, as using MCP servers could be overwhelming for specific tasks.

I would like to be able to run like opencode --disable-mcp run "say hello" for instance.