How to verify PGP detached signature using Bouncycastle

I want to parse and verify an OpenPGP detached signature using Bouncycastle. The signature would be something like this:

-----BEGIN PGP SIGNATURE-----
Version: fast-openpgp

wsBcBAABCAAQBQJfRm9jCRDzeoZuOgUYnQAAVkoIAEReZ6Pp3SimYKbH+JHzwW8q
LiWeQIPNatFwDQHgD4ipT9aXMaObnXXl83KUQ5lPx8Bw77BxParpUbtCRNTrWoU5
XZ1ikfqzmeVEJrk4YsNKDiBpvjbyF86F8KSkXhwdLWSm1e6yemnXKcTHg2L13AiS
6TIqXXbcRmFF7RTO4DQrjira2YYlW8eHPIcCmOq0YjR4Qpz+R/+3BlfV2TAcL/sd
SeKAczgvdP6CS6be1rPA0nlgw9T853BpgqplQVM30pUhVlni7ga1YRzENm6Qic5A
uEbmPyunim2WHytPuLQq+BQvAq+Wrr2kiM7DhyvYFihDNdFWW67Y+fSlgPxOi/8=
=QKpc
-----END PGP SIGNATURE-----

And here is how I try to create CMSSignedData in Kotlin:

fun verifyDetached(signatureString: String, dataString: String): Boolean {
    val dataBytes = dataString.toByteArray()
    val signatureBytes = signatureString.toByteArray()
    val processableDataBytes = CMSProcessableByteArray(dataBytes)
    val ci = ContentInfo.getInstance(ASN1Sequence.fromByteArray(signatureBytes))
    val cms = CMSSignedData(processableDataBytes, ci)
    ...
}

When I pass the whole signature block into the function (including -----BEGIN PGP SIGNATURE-----) I get java.io.IOException: unknown tag 13 encountered.

When I remove signature wrappers and just pass in the signature content into the function I get java.io.IOException: Extra data detected in stream at org.bouncycastle.asn1.ASN1Primitive.fromByteArray.

When I directly pass signatureBytes to CMSSignedData constructor I get java.lang.IllegalArgumentException: unknown object in getInstance: org.bouncycastle.asn1.DLApplicationSpecific.

How should I verify this kind of signature using Bouncycastle?

CMS is completely and totally different from and not related to PGP. For PGP use the BouncyCastle implementation of PGP in bcpg, NOT the implementation of CMS in bcpkix. See e.g. https://stackoverflow.com/questions/42170230/verification-of-pgp-signature-using-bouncycastle and https://stackoverflow.com/questions/57574714/how-to-sign-and-verify-the-file-in-java .