feat(api): expand API endpoints for repo, PR, user, workspace management

- Add git operation endpoints: archive, compare branches, diff, tree,
  repository extras
- Add repo endpoints: contributors, delete fork, get branch/commit
  status/deploy key/invitation/member/release/tag/webhook, topics,
  release assets, webhook deliveries/retry
- Add PR endpoints: review requests, templates
- Add user endpoints: block/unblock, follow/unfollow, presence,
  personal access tokens, account restore
- Add workspace endpoints: billing history, approvals, domains,
  integrations, invitations, members, webhooks, restore
- Add internal API, notification API, IM API modules
- Update route configuration and OpenAPI spec

api/notify/list_templates.rs

@@ -0,0 +1,48 @@
+use actix_web::{HttpResponse, web};
+use serde::Deserialize;
+use utoipa::IntoParams;
+
+use crate::api::response::{ApiErrorResponse, ApiResponse};
+use crate::error::AppError;
+use crate::models::notifications::NotificationTemplate;
+use crate::service::AppService;
+use crate::session::Session;
+
+#[derive(Debug, Deserialize, IntoParams)]
+pub struct QueryParams {
+    pub limit: Option<i64>,
+    pub offset: Option<i64>,
+}
+
+/// List notification templates (requires system admin)
+#[utoipa::path(
+    get,
+    path = "/api/v1/notifications/templates",
+    tag = "Notifications",
+    operation_id = "notificationListTemplates",
+    params(QueryParams),
+    responses(
+        (status = 200, description = "Templates listed successfully", body = ApiResponse<Vec<NotificationTemplate>>),
+        (status = 401, description = "Authentication required or session expired", body = ApiErrorResponse),
+        (status = 403, description = "System admin access required", body = ApiErrorResponse),
+        (status = 500, description = "Internal server error", body = ApiErrorResponse),
+    ),
+    security(
+        ("session_cookie" = [])
+    )
+)]
+pub async fn list_templates(
+    service: web::Data<AppService>,
+    session: Session,
+    query: web::Query<QueryParams>,
+) -> Result<HttpResponse, AppError> {
+    let result = service
+        .notify
+        .list_templates(
+            &session,
+            query.limit.unwrap_or(50),
+            query.offset.unwrap_or(0),
+        )
+        .await?;
+    Ok(HttpResponse::Ok().json(ApiResponse::new(result)))
+}