fix: implement Display trait for ServiceError enum

apps/api/src/errors/service_error.rs

@@ -15,6 +15,20 @@ impl From<Box<dyn std::error::Error + Send + Sync + 'static>> for ServiceError {
     }
 }
 
+impl std::fmt::Display for ServiceError {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        match self {
+            ServiceError::NotFound(msg) => write!(f, "Not Found: {}", msg),
+            ServiceError::DatabaseError(msg) => write!(f, "Database Error: {}", msg),
+            ServiceError::Unauthorized(msg) => write!(f, "Unauthorized: {}", msg),
+            ServiceError::InternalError(msg) => write!(f, "Internal Error: {}", msg),
+            ServiceError::BadRequest(msg) => write!(f, "Bad Request: {}", msg),
+        }
+    }
+}
+
+impl std::error::Error for ServiceError {}
+
 impl From<DbErr> for ServiceError {
     fn from(err: DbErr) -> Self {
         match err {