fix(mail/delivery): Centralize runtime/plugin imports and switch modules to use plugins exports; unify EventEmitter usage; update Deno dependencies and small path/server refactors

ts/mail/delivery/smtpserver/data-handler.ts

@@ -4,8 +4,6 @@
  */
 
 import * as plugins from '../../../plugins.ts';
-import * as fs from 'fs';
-import * as path from 'path';
 import { SmtpState } from './interfaces.ts';
 import type { ISmtpSession, ISmtpTransactionResult } from './interfaces.ts';
 import type { IDataHandler, ISmtpServer } from './interfaces.ts';