feat: Partial support for unnamed packages

* Change PackageId to support both named and unnamed package
* Update the package resolver logic with unnamed package support
* Update the "package download" command

lib/backend-api/src/types.rs

@@ -92,6 +92,7 @@ mod queries {
         pub updated_at: DateTime,
         pub tag: String,
         pub is_archived: bool,
+        pub webc_url: String,
     }
 
     #[derive(cynic::QueryFragment, Debug, Clone, Serialize)]