To identify whether your local repository has signing enabled, look for the signature in one of the packages in the repository.
You can view the signature for a package under the dist object in the package metadata JSON file, for example:
"dist":{
..omitted..,
"signatures": [{
"keyid": "SHA256:{{SHA256_PUBLIC_KEY}}",
"sig": "a312b7c3cb4a1b693e8ebac5ee1ca9cc01g2661c14381917dcb111517f72370809..."
}],