Make ctap2::CtapMappingError private

The type is only used internally and does not have to be part of the
public API.

CHANGELOG.md

@@ -10,6 +10,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 - Remove unused `Rpc` trait.
 - Remove `cbor-smol` re-export as `serde`.
+- Make `ctap2::CtapMappingError` private.
 
 ## [0.6.0-rc.4] 2026-06-01
 

src/ctap2.rs

@@ -53,7 +53,7 @@ pub enum Request<'a> {
     Vendor(crate::operation::VendorOperation),
 }
 
-pub enum CtapMappingError {
+enum CtapMappingError {
     InvalidCommand(u8),
     ParsingError(cbor_smol::Error),
 }