mcp: support auth provider by HTTP basic auth

[lambochen]

Support a way to auth client-server connection by request params.
I think it's necessary, such as, When using Claude Desktop to connect to a remote MCP Server, only one URL can be filled in. If identity authentication and authorization are implemented, passing information from the request parameters is a good choice.

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[lambochen]

Issue: #2888

[lambochen]

McpServerAuthProvider example

McpServerAuthProvider implement example

import io.modelcontextprotocol.server.McpServerAuthParam;
import io.modelcontextprotocol.server.McpServerAuthProvider;
import org.springframework.stereotype.Component;

@Component
public class CustomMcpServerAuthProvider implements McpServerAuthProvider {

	@Override
	public boolean authenticate(McpServerAuthParam param) {
		// example: get token param
		String token = param.getParams().get("token");
		// TODO do something
		return true;
	}

}

MCP Client(eg: Claude) config

{
  "mcpServers": {
    "mcp-remote-server-example": {
      "url": "http://{your mcp server}/sse?token=xxx"
    }
  }
}