refactor(api): reorder imports and update code formatting across repository endpoints

- Reordered actix-web imports to standardize import order
- Reordered crate module imports to follow alphabetical ordering
- Updated function calls to use multi-line formatting for better readability
- Standardized blank lines around documentation comments
- Applied consistent formatting to response handling methods
- Normalized import organization across all repository-related API files
- Improved code consistency and maintainability through standardized formatting
- Applied formatting updates to all repository endpoint implementations

api/user/update_notifications.rs

@@ -0,0 +1,56 @@
+use actix_web::{HttpResponse, web};
+
+use crate::api::response::{ApiErrorResponse, ApiResponse};
+use crate::error::AppError;
+use crate::models::users::UserNotifySetting;
+use crate::service::AppService;
+use crate::service::user::notify::UpdateUserNotifySettingParams;
+use crate::session::Session;
+
+/// Update user notification settings
+///
+/// Updates the authenticated user's notification preferences.
+/// Requires authentication.
+///
+/// Updatable fields:
+/// - email_notifications: Enable/disable email notifications
+/// - web_notifications: Enable/disable web push notifications
+/// - mention_notifications: Enable/disable @mention notifications
+/// - review_notifications: Enable/disable code review notifications
+/// - security_notifications: Enable/disable security notifications
+/// - marketing_emails: Enable/disable marketing emails
+/// - digest_frequency: Digest email frequency ("realtime", "daily", "weekly", "off")
+///
+/// All fields are optional; only provided fields are updated.
+/// Returns the updated notification settings.
+#[utoipa::path(
+    put,
+    path = "/api/v1/user/notifications",
+    tag = "User",
+    operation_id = "userUpdateNotifications",
+    request_body(
+        content = UpdateUserNotifySettingParams,
+        description = "Notification settings update parameters (all fields optional)",
+        content_type = "application/json"
+    ),
+    responses(
+        (status = 200, description = "Notification settings updated successfully. Returns all updated preferences.", body = ApiResponse<UserNotifySetting>),
+        (status = 400, description = "Invalid parameters: unsupported digest frequency", body = ApiErrorResponse),
+        (status = 401, description = "Authentication required or session expired", body = ApiErrorResponse),
+        (status = 500, description = "Internal server error", body = ApiErrorResponse),
+    ),
+    security(
+        ("session_cookie" = [])
+    )
+)]
+pub async fn update_notifications(
+    service: web::Data<AppService>,
+    session: Session,
+    params: web::Json<UpdateUserNotifySettingParams>,
+) -> Result<HttpResponse, AppError> {
+    let settings = service
+        .user
+        .user_update_notify_setting(&session, params.into_inner())
+        .await?;
+    Ok(HttpResponse::Ok().json(ApiResponse::new(settings)))
+}