feat: add data dir option

main.ts

@@ -4,6 +4,7 @@ import { StdioServerTransport } from "@modelcontextprotocol/sdk/server/stdio.js"
 import { Command } from "commander";
 import crypto from "node:crypto";
 import http from "node:http";
+import { initDataDir } from "./ews_client.ts";
 import { registerAuthTools } from "./tools/auth.ts";
 import { registerEmailTools } from "./tools/email.ts";
 import { registerFolderTools } from "./tools/folders.ts";
@@ -17,11 +18,14 @@ const program = new Command()
     "SHA-256 hash of bearer token for HTTP transport auth",
   )
   .option("--host <host>", "HTTP host", "127.0.0.1")
-  .option("--port <port>", "HTTP port", "8000");
+  .option("--port <port>", "HTTP port", "8000")
+  .option("--data-dir <path>", "Data directory for config.json", "./data");
 
 program.parse(process.argv);
 const options = program.opts();
 
+initDataDir(options.dataDir);
+
 function buildServer(): McpServer {
   const server = new McpServer({
     name: "exchange-mcp",