Issue 762 (#763)

* Add InvalidRangeSpec error

* Add EntityTooSmall to from_u32

* Add InvalidRangeSpec to from_u32

* Map InvalidRangeSpec to correct S3ErrorCode

* Return Error::InvalidRangeSpec

* Use auto implementation

---------

Co-authored-by: Niklas Mollenhauer <nikeee@outlook.com>

crates/kms/src/config.rs

@@ -21,21 +21,15 @@ use std::time::Duration;
 use url::Url;
 
 /// KMS backend types
-#[derive(Debug, Clone, Serialize, Deserialize, PartialEq, Eq)]
+#[derive(Debug, Default, Clone, Serialize, Deserialize, PartialEq, Eq)]
 pub enum KmsBackend {
     /// Vault backend (recommended for production)
     Vault,
     /// Local file-based backend for development and testing only
+    #[default]
     Local,
 }
 
-impl Default for KmsBackend {
-    fn default() -> Self {
-        // Default to Local backend since Vault requires configuration
-        Self::Local
-    }
-}
-
 /// Main KMS configuration
 #[derive(Debug, Clone, Serialize, Deserialize)]
 pub struct KmsConfig {