Antlr 4.13.0 typescript target introduced invalid module configuration

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Hi,



This [PR](https://github.com/antlr/antlr4/pull/4217/files#diff-7c99c0b7a2507f0ed32c83f5634f6d281157f04c1391820f3ccb734bbb7652fb) introduces a bug in the npm package definition.



In the `exports` section of the package.json file the file referenced in the `node`/`browser` sections does not exist.



```

  "exports": {

    ".": {

      "node": {

        "types": "src/index.node.d.ts",

        "import": "./dist/antlr4.node.mjs",

        "require": "./dist/antlr4.node.cjs",

        "default": "./dist/antlr4.node.mjs"

      },

      "browser": {

        "types": "src/index.web.d.ts",

        "import": "./dist/antlr4.web.mjs",

        "require": "./dist/antlr4.web.cjs",

        "default": "./dist/antlr4.web.mjs"

      }

    }

```



`src/index.node.d.ts` and `src/index.web.d.ts` does not exist in the shipped package. All files in the `src` directory in the released module is located in `src/antlr4`, and even here there is no combined definition files.



Unless you create a combined file the intention is maybe to point this path at `src/antlr4/index.d.ts`? 

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