Add Svelte support

Hi, Support for svelte does not seem to be working.

Adding this:

```json
"Svelte": {
    "language_servers": ["svelte-language-server", "intl-lens"],
    "inlay_hints": {
        "enabled": true,
    },
},
```

Does not seem to work, and I'm not sure if it is able to parse the syntax.
This would be great to have!