Revamp admin dashboard analytics and UI

Refactored the admin dashboard to use tabbed navigation for analytics and management. Enhanced AdminAnalytics with Recharts visualizations, added top vendors by revenue, and improved chart tooltips. Removed unused columns from vendor table. Updated layout and notification context to exclude admin pages from dashboard-specific UI and notifications. Minor debug logging added to SystemStatusCard.

app/dashboard/admin/vendors/page.tsx

@@ -130,8 +130,6 @@ export default async function AdminVendorsPage() {
                 <TableHead>Store</TableHead>
                 <TableHead>Status</TableHead>
                 <TableHead>Join Date</TableHead>
-                <TableHead>Orders</TableHead>
-                <TableHead>Revenue</TableHead>
                 <TableHead className="text-right">Actions</TableHead>
               </TableRow>
             </TableHeader>
@@ -139,10 +137,7 @@ export default async function AdminVendorsPage() {
               {vendors.map((vendor) => (
                 <TableRow key={vendor._id}>
                   <TableCell>
-                    <div>
-                      <div className="font-medium">{vendor.username}</div>
-                      <div className="text-sm text-muted-foreground">{vendor.email || 'No email'}</div>
-                    </div>
+                    <div className="font-medium">{vendor.username}</div>
                   </TableCell>
                   <TableCell>{vendor.storeId || 'No store'}</TableCell>
                   <TableCell>
@@ -162,8 +157,6 @@ export default async function AdminVendorsPage() {
                   <TableCell>
                     {vendor.createdAt ? new Date(vendor.createdAt).toLocaleDateString() : 'N/A'}
                   </TableCell>
-                  <TableCell>N/A</TableCell>
-                  <TableCell>N/A</TableCell>
                   <TableCell className="text-right">
                     <div className="flex items-center justify-end space-x-2">
                       <Button variant="outline" size="sm">