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/admin-providers-wrapper.tsx

@@ -0,0 +1,26 @@
+'use client'
+
+import { LanguageProvider } from '@/lib/i18n/LanguageProvider'
+import type { Translations } from '@/lib/i18n/load-translations'
+import type { ReactNode } from 'react'
+
+interface AdminProvidersWrapperProps {
+  children: ReactNode
+  initialLanguage?: string
+  initialTranslations?: Translations
+}
+
+export function AdminProvidersWrapper({
+  children,
+  initialLanguage = 'en',
+  initialTranslations,
+}: AdminProvidersWrapperProps) {
+  return (
+    <LanguageProvider
+      initialLanguage={initialLanguage as any}
+      initialTranslations={initialTranslations}
+    >
+      {children}
+    </LanguageProvider>
+  )
+}