Integrate shadcn UI & add UI primitives

Integrates the shadcn/ui design system across the app and adds a collection of reusable UI primitives and layout components. Adds new UI atoms/molecules (avatar, card, collapsible, progress, select, sheet, sidebar, skeleton, table, tabs, toggles, tooltip), app sidebar, media filters, MediaTable, and a mobile hook; updates many views/components to use the new UI. Updates AGENTS.md with styling, layout, accessibility and design standards (Tailwind/shadcn guidance) and adds a registry entry to components.json. Also updates dependencies/lockfile to align shadcn and related packages.

src/main.tsx

@@ -2,9 +2,12 @@ import {StrictMode} from 'react';
 import {createRoot} from 'react-dom/client';
 import App from './App.tsx';
 import './index.css';
+import { TooltipProvider } from '@/components/ui/tooltip';
 
 createRoot(document.getElementById('root')!).render(
   <StrictMode>
-    <App />
+    <TooltipProvider>
+      <App />
+    </TooltipProvider>
   </StrictMode>,
 );