feat: add TypeScript config file support

[xbinaryx]

Prerequisites checklist

• I have read the contributing guidelines.

What is the purpose of this pull request?

This PR adds support for generating TypeScript configuration files in the config generator.

What changes did you make? (Give an overview)

• Added a prompt for users to select the language of their configuration file (JavaScript or TypeScript) if TypeScript is enabled.
• Implemented logic to generate eslint.config.ts (or eslint.config.mts for CommonJS) when TypeScript is selected.
• Added a conditional prompt for users to add Jiti as a devDependency if they choose a TypeScript config file and are running Node.js <24.3.0, since Jiti is required to load TypeScript config files in those environments.
• Added snapshot tests

Related Issues

Fixes #177

[JoshuaKGoldberg]

Looking good, thanks! I left a couple of suggestions that I think should land, but I'm not deeply familiar with this project and want to defer to a second team member's opinion.

[aladdin-add]

LGTM. Waiting a few days for other reviewers before merging.

[aladdin-add]

for reviewers:

@eslint/create-config: v1.9.0

√ What do you want to lint? · javascript
√ How would you like to use ESLint? · problems
√ What type of modules does your project use? · esm
√ Which framework does your project use? · none
√ Does your project use TypeScript? · No / Yes
√ Where does your code run? · browser
√ Which language do you want your configuration file be written in? · ts
Jiti is required for Node.js <24.3.0 to read TypeScript configuration files.
√ Would you like to add Jiti as a devDependency? · No / Yes
The config that you've selected requires the following dependencies:

eslint, @eslint/js, globals, typescript-eslint, jiti
√ Would you like to install them now? · No / Yes
√ Which package manager do you want to use? · npm