support curation for Swift packages

Is there any plan to support **Swift packages** as a harvest source in ClearlyDefined?

I tried to curate data for the following PURL:
`pkg:swift/github.com/apple/swift-protobuf@1.31.1`:

```bash
curl -X GET "https://api.clearlydefined.io/definitions/syft/github.com/apple/swift-protobuf/1.31.1" -H "accept: */*" | jq .
```

The response was:
```bash
% Total % Received % Xferd Average Speed Time Time Time Current
Dload Upload Total Spent Left Speed
100 74 100 74 0 0 39 0 0:00:01 0:00:01 --:--:-- 39
{
"error": {
"code": "500",
"message": "An error has occurred",
"innererror": {}
}
}

```

From the [Adding a Harvest source](https://docs.clearlydefined.io/docs/get-involved/adding-sources), I see support for ecosystems like `npm`, `maven`, `pypi`, `nuget`, `git`, etc., but I don’t see `Swift` listed.