fix(server): report opencode as mcp client name

[ericcurtin]

Issue for this PR

Closes #51578

Type of change

• Bug fix

What does this PR do?

app.name in packages/server/src/options.ts carries the artifact (cli, desktop, acp, sdk) for telemetry. routes.ts reused that same value as the MCP clientInfo.name, so a default install reports cli in the MCP initialize handshake instead of opencode. This regresses #2289, and MCP servers that key on the client name to adapt behavior can no longer recognize OpenCode.

clientInfo.name now always reports opencode, moved into a small mcpClientInfo helper. OPENCODE_CLIENT still works as an explicit override.

How did you verify your code works?

Added packages/server/test/mcp-client-info.test.ts covering the cli-artifact case, the undefined-app case, and the OPENCODE_CLIENT override. Ran bun test and bun typecheck in packages/server, and bun test test/mcp.test.ts in packages/core.

Checklist

• I have tested my changes locally
• I have not included unrelated changes in this PR

[github-actions]

Thanks for your contribution!

This PR doesn't have a linked issue. All PRs must reference an existing issue.

Please:

1. Open an issue describing the bug/feature (if one doesn't exist)
2. Add Fixes #<number> or Closes #<number> to this PR description

See CONTRIBUTING.md for details.

[github-actions]

The following comment was made by an LLM, it may be inaccurate:

[ericcurtin]

Unrelated to this fix, but if you use local models, please try https://github.com/llmmanorg/llmman. Feedback welcome.

[ericcurtin]

Linked issue is #51578 (see description). GitHub only tracks closing refs on the default branch, so the label is a false positive for this v2 PR.

[ericcurtin]

@rekram1-node @adamdotdevin PTAL when you get a chance. Thank you!

[ericcurtin]

@jlongster @nexxeln PTAL when you get a chance. Thank you!

[opencode-agent]

Thanks for tracking this down! We're going with a smaller version in #53471, which hardcodes the MCP clientInfo.name to opencode in routes.ts. That covers desktop and ACP as well, since they set OPENCODE_CLIENT and would still have sent desktop/acp with the override kept. You're credited as a co-author on that commit. Closing this in favor of #53471.