import { Effect } from "effect";import * as http from "node:http";import { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";import { StreamableHTTPServerTransport } from "@modelcontextprotocol/sdk/server/streamableHttp.js"; export type McpTestServer = {  readonly url: string;  readonly httpServer: http.Server;  /** Number of MCP sessions created (each connect = 1 session) */  readonly sessionCount: () => number;}; export const serveMcpServer = (factory: () => McpServer) =>  Effect.acquireRelease(    Effect.callback<McpTestServer, Error>((resume) => {      const transports = new Map<string, StreamableHTTPServerTransport>();      let sessions = 0;       const httpServer = http.createServer(async (req, res) => {        const sessionId = req.headers["mcp-session-id"] as string | undefined;         if (sessionId) {          const transport = transports.get(sessionId);          if (!transport) {            res.writeHead(404);            res.end("Session not found");            return;          }          await transport.handleRequest(req, res);          return;        }         const mcpServer = factory();        sessions++;         const transport = new StreamableHTTPServerTransport({          sessionIdGenerator: () => crypto.randomUUID(),          onsessioninitialized: (sid) => {            transports.set(sid, transport);          },        });         await mcpServer.connect(transport);        await transport.handleRequest(req, res);      });       httpServer.listen(0, () => {        const addr = httpServer.address();        const port = typeof addr === "object" && addr ? addr.port : 0;        resume(          Effect.succeed({            url: `http://127.0.0.1:${port}`,            httpServer,            sessionCount: () => sessions,          }),        );      });    }),    ({ httpServer }) =>      Effect.sync(() => {        httpServer.close();      }),  );