No OpenCode mcp config information in README

[sin4ch]

Is your feature request related to a problem? Please describe.

Hi. I noticed that in the README, nearly every other IDE/coding agent is included in the client configuration section except OpenCode.

Describe the solution you'd like

I'm submitting a PR now to fix that.

I'll be linking to OpenCode's official MCP and Config documentation to help others properly configure the MCP server with OpenCode.

Describe alternatives you've considered

No alternatives.

Additional context

No response