feat: auth & admin

.agents/skills/vercel-react-best-practices/rules/rendering-hydration-no-flicker.md

@@ -14,13 +14,9 @@ When rendering content that depends on client-side storage (localStorage, cookie
 ```tsx
 function ThemeWrapper({ children }: { children: ReactNode }) {
   // localStorage is not available on server - throws error
-  const theme = localStorage.getItem('theme') || 'light'
-  
-  return (
-    <div className={theme}>
-      {children}
-    </div>
-  )
+  const theme = localStorage.getItem('theme') || 'light';
+
+  return <div className={theme}>{children}</div>;
 }
 ```
 
@@ -30,21 +26,17 @@ Server-side rendering will fail because `localStorage` is undefined.
 
 ```tsx
 function ThemeWrapper({ children }: { children: ReactNode }) {
-  const [theme, setTheme] = useState('light')
-  
+  const [theme, setTheme] = useState('light');
+
   useEffect(() => {
     // Runs after hydration - causes visible flash
-    const stored = localStorage.getItem('theme')
+    const stored = localStorage.getItem('theme');
     if (stored) {
-      setTheme(stored)
+      setTheme(stored);
     }
-  }, [])
-  
-  return (
-    <div className={theme}>
-      {children}
-    </div>
-  )
+  }, []);
+
+  return <div className={theme}>{children}</div>;
 }
 ```
 
@@ -56,9 +48,7 @@ Component first renders with default value (`light`), then updates after hydrati
 function ThemeWrapper({ children }: { children: ReactNode }) {
   return (
     <>
-      <div id="theme-wrapper">
-        {children}
-      </div>
+      <div id="theme-wrapper">{children}</div>
       <script
         dangerouslySetInnerHTML={{
           __html: `
@@ -73,7 +63,7 @@ function ThemeWrapper({ children }: { children: ReactNode }) {
         }}
       />
     </>
-  )
+  );
 }
 ```