Clarify OpenCode support for the Upgrade MCP workflow #56

I currently use the Modernization integration in Copilot CLI and would like to use its successor with OpenCode 1.19.0 on Windows.

I would prefer an upstream-supported integration rather than maintaining converted agents or custom adapters.

The legacy Modernization MCP package documents manual MCP configuration, and dotnet/modernize-dotnet now directs users to this repository. Could you clarify whether the Upgrade MCP workflow supports non-Copilot clients such as OpenCode?

In particular:

• Setup: What are the supported launch commands and required companion servers?
• Client identification: Should APPMOD_CALLER_TYPE be omitted, or is there a supported value for OpenCode? I do not want to identify OpenCode as copilot-cli.
• Authentication and model access: Does the server require credentials or model configuration separate from the host? OpenCode 1.19.0 does not advertise MCP sampling; is there a supported alternative?
• Workflow: Can assessment, planning, execution and resume work without Copilot-specific agent definitions, hooks or dashboard integration?

I have not run the Upgrade servers in OpenCode yet, so this is a compatibility/support request rather than a report of a confirmed runtime defect.

An official OpenCode configuration example and a clear statement of supported functionality would help.

AI-assisted report prepared with OpenCode.