Fix sticky positioning of version and storage info in admin sidebar

- Change AdminLayout to use h-screen instead of min-h-screen
- Add overflow-hidden to prevent scrollbar on outer container
- Update sidebar to use h-screen for proper height reference
- Add flex-shrink-0 to header and bottom sections
- Add min-h-0 to navigation to allow proper overflow
- Add overflow-y-auto to main content area

The version info and storage usage now properly stick to the bottom of the viewport instead of the bottom of the page content.

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

frontend/src/components/admin/AdminLayout.tsx

@@ -30,7 +30,7 @@ export const AdminLayout: React.FC = () => {
   }
 
   return (
-    <div className="min-h-screen bg-neutral-50 flex">
+    <div className="h-screen bg-neutral-50 flex overflow-hidden">
       {/* Mobile sidebar backdrop */}
       {sidebarOpen && (
         <div
@@ -43,7 +43,7 @@ export const AdminLayout: React.FC = () => {
       <AdminSidebar isOpen={sidebarOpen} onClose={() => setSidebarOpen(false)} />
 
       {/* Main content */}
-      <div className="flex-1 flex flex-col min-w-0">
+      <div className="flex-1 flex flex-col min-w-0 h-screen">
         {/* Header */}
         <AdminHeader onMenuClick={() => setSidebarOpen(true)} />
         
@@ -51,7 +51,7 @@ export const AdminLayout: React.FC = () => {
         <MaintenanceBanner />
 
         {/* Page content */}
-        <main id="main-content" className="flex-1 px-4 sm:px-6 lg:px-8 py-8">
+        <main id="main-content" className="flex-1 px-4 sm:px-6 lg:px-8 py-8 overflow-y-auto">
           <Outlet />
         </main>
       </div>