style: apply rustfmt formatting to fix CI

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/infrastructure/services/file_system_i18n_service.rs

@@ -1,8 +1,8 @@
 use serde_json::Value;
 use std::collections::HashMap;
 use std::path::PathBuf;
-use tokio::sync::RwLock;
 use tokio::fs;
+use tokio::sync::RwLock;
 
 use crate::domain::services::i18n_service::{I18nError, I18nResult, I18nService, Locale};