fix: resolve React Error #310 and refactor admin section

- Fix React bug #33580: remove Suspense boundaries co-located with Link components
- Delete settings/loading.tsx and admin/loading.tsx (root cause of race condition)
- Convert all admin navigation from Next.js Link to anchor tags
- Move admin pages to dedicated (admin) route group
- Add AdminHeader matching main header visual design
- Add AdminSidebar with anchor-based navigation
- Add /api/admin/models route handler (replaces server actions for GET)
- Add /api/debug/client-error for server-side browser error reporting
- Add useNoteRefreshOptional() to fix crash in AdminHeader
- Hide Admin Dashboard menu for non-admin users
- Change app icons from yellow to blue (#3A7CA5) matching brand primary
- Fix admin search bar width to match main header

Made-with: Cursor

memento-note/components/sidebar.tsx

@@ -26,7 +26,7 @@ import { useHomeViewOptional } from '@/context/home-view-context'
 import { useEffect, useState } from 'react'
 import { getTrashCount } from '@/app/actions/notes'
 
-const HIDDEN_ROUTES = ['/agents', '/chat', '/lab']
+const HIDDEN_ROUTES = ['/agents', '/chat', '/lab', '/admin']
 
 export function Sidebar({ className, user }: { className?: string, user?: any }) {
   const pathname = usePathname()
@@ -36,10 +36,15 @@ export function Sidebar({ className, user }: { className?: string, user?: any })
   const homeBridge = useHomeViewOptional()
   const [trashCount, setTrashCount] = useState(0)
 
-  // Fetch trash count
+  const searchKey = searchParams.toString()
+
+  // Fetch trash count — skip for hidden/admin routes to avoid dispatching a
+  // Server Action during an ongoing App Router navigation transition, which
+  // would increment React's nested-update counter and trigger Error #310.
   useEffect(() => {
+    if (HIDDEN_ROUTES.some(r => pathname.startsWith(r))) return
     getTrashCount().then(setTrashCount)
-  }, [pathname, searchParams])
+  }, [pathname, searchKey])
 
   // Hide sidebar on Agents, Chat IA and Lab routes
   if (HIDDEN_ROUTES.some(r => pathname.startsWith(r))) return null