⚙️ Revert untagged enum - use standard TOML enum format

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Co-Authored-By: Claude <[email protected]>

Author: ismoilovdevml

src/configuration.rs

@@ -533,7 +533,6 @@ impl TryFrom<(String, Value)> for Box<dyn Middleware> {
 }
 
 #[derive(Debug, Deserialize)]
-#[serde(untagged)]
 pub enum CertificateConfig {
     Local {
         certificate_path: String,