Incorrect type for `flat/recommended` configuration

The type currently set for the [`flat/recommended` configuration](https://github.com/edvardchen/eslint-plugin-i18next/blob/main/lib/index.d.ts) is `ESLint.ConfigData`. This results in type errors when importing into a flat file. <img width="1141" alt="Image" src="https://github.com/user-attachments/assets/c2f8329c-d76e-43de-acfb-b2113a72c3f0" /> According to the [ESLint documentation](https://eslint.org/docs/latest/use/configure/migration-guide#typescript-types-for-flat-config-files), flat configuration files should use the `Linter.Config` type. I've verified that updating the type fixes the issue.