RepoNameError has no miette span/label/source_code fields, so there
is nothing for diagnostic(transparent) to propagate. Only
#[error(transparent)] is needed here, consistent with Secret, Sql,
Yaml, and Utf8 which follow the same pattern.

diff --git a/quire-server/src/error.rs b/quire-server/src/error.rs
index bc742cb..cf07e44 100644
--- a/quire-server/src/error.rs
+++ b/quire-server/src/error.rs
@@ -13,7 +13,6 @@ pub enum Error {
     ConfigNotFound(String),
 
     #[error(transparent)]
-    #[diagnostic(transparent)]
     Repo(#[from] RepoNameError),
 
     #[error(transparent)]