Make the auction introduction screen use the entire screen width

Modify the `Auctions.tsx` file to remove max-width and left/right padding from the main content area, allowing it to span the full screen width.

Replit-Commit-Author: Agent
Replit-Commit-Session-Id: 069d4324-6c40-4355-955e-c714a50de1ea
Replit-Commit-Checkpoint-Type: full_checkpoint
Replit-Commit-Screenshot-Url: https://storage.googleapis.com/screenshot-production-us-central1/3df548ff-50ae-432f-9be4-25d34eccc983/069d4324-6c40-4355-955e-c714a50de1ea/yHCvWBg

client/src/pages/Auctions.tsx

@@ -416,7 +416,7 @@ export default function Auctions() {
         </div>
       </header>
 
-      <main className="flex-1 max-w-7xl mx-auto px-4 py-3 w-full">
+      <main className="flex-1 px-6 py-3 w-full">
         {/* Auction Explanation */}
         <div className="mb-4">
           <Card>