Add API Status Indicator to AppSidebar and enhance ApiMonitor with localStorage support for auto-refresh and refresh interval settings

frontend/src/layout/AppSidebar.tsx

@@ -20,6 +20,7 @@ import { useSidebar } from "../context/SidebarContext";
 import SidebarWidget from "./SidebarWidget";
 import { APP_VERSION } from "../config/version";
 import { useAuthStore } from "../store/authStore";
+import ApiStatusIndicator from "../components/sidebar/ApiStatusIndicator";
 
 type NavItem = {
   name: string;
@@ -495,6 +496,8 @@ const AppSidebar: React.FC = () => {
         )}
       </div>
       <div className="flex flex-col overflow-y-auto duration-300 ease-linear no-scrollbar">
+        {/* API Status Indicator - above OVERVIEW section */}
+        <ApiStatusIndicator />
         <nav className="mb-6">
           <div className="flex flex-col gap-2">
             {allSections.map((section, sectionIndex) => (