Fix: mcp-remote OAuth connection now works with the 2025-11-25 MCP protocol

Adding Vello as an MCP server via mcp-remote was silently failing before the OAuth flow could start. The MCP client validates the server's OAuth discovery document and requires a jwks_uri field — we were omitting it. The discovery document now includes the correct JWKS endpoint, letting the OAuth handshake complete and mcp-remote connect successfully.