"basic"/"relative" moduleResolution

### 🔍 Search Terms

module resolution, relative paths

### ✅ Viability Checklist

- [x] This wouldn't be a breaking change in existing TypeScript/JavaScript code
- [x] This wouldn't change the runtime behavior of existing JavaScript code
- [x] This could be implemented without emitting different JS based on the types of the expressions
- [x] This isn't a runtime feature (e.g. library functionality, non-ECMAScript syntax with JavaScript output, new syntax sugar for JS, etc.)
- [x] This isn't a request to add a new utility type: https://github.com/microsoft/TypeScript/wiki/No-New-Utility-Types
- [x] This feature would agree with the rest of our Design Goals: https://github.com/Microsoft/TypeScript/wiki/TypeScript-Design-Goals

### ⭐ Suggestion

Hi all, I am writing a custom JavaScript runtime that only supports module imports using relative paths with file extensions present.

This is akin to browser-based module resolution (minus import maps).

At present, the `compilerOptions.moduleResolution` settings are:
- classic (deprecated)
- node/node10
- node16
- nodenext
- bundler

I think `classic` might work but am hesitant to use a deprecated feature.

Could we include a
```json
{
"compilerOptions": {
"moduleResolution": "relative"
}
}
```

That _only_ permits resolving module import paths that are relative to the current file and requires that import paths include file extensions?

```typescript
import * as foo from "./foo.js" // 👍
import * as foo from "./foo.ts" // 👍

import * as foo from "./foo" // 👎
import * as foo from "foo" // 👎
```

### 📃 Motivating Example

- Browsers using JavaScript modules without a bundler
- Custom JavaScript resolution algorithms
- (shameless plug) https://github.com/alshdavid/ion

### 💻 Use Cases

1. Accurate import semantics for consumers not using Node.js or contexts compatible with Node.js import resolution semantics

Commencez par lire comment le compilateur gère les options de résolution de modules existantes classic, node10, node16, nodenext et bundler. Suivez le point d’entrée compilerOptions.moduleResolution et comparez les tests actuels pour les imports relatifs et de packages. Le travail est terminé lorsqu’un nouveau mode relatif accepte les imports relatifs avec extension tout en rejetant les imports sans extension et les imports non relatifs, avec une couverture pour les exemples demandés.

Rédigé par le modèle d'indexation à partir du texte de l'issue.