Remove grid functionality from the pixel art creation platform

Removes the grid display option, grid toggle button, and related configuration settings from the canvas component, CSS, and server configuration files.

Replit-Commit-Author: Agent
Replit-Commit-Session-Id: 0385ea33-cde8-4bbd-8fce-8d192d30eb41
Replit-Commit-Checkpoint-Type: full_checkpoint
Replit-Commit-Screenshot-Url: https://storage.googleapis.com/screenshot-production-us-central1/870d08ce-da3b-4822-9874-c2fe2b7628b1/0385ea33-cde8-4bbd-8fce-8d192d30eb41/Zffw2vY

client/src/components/canvas.tsx

@@ -7,7 +7,7 @@ interface CanvasProps {
   selectedColor: string;
   canvasWidth: number;
   canvasHeight: number;
-  showGrid: boolean;
+
   onPixelClick: (x: number, y: number) => void;
   cooldownActive: boolean;
 }
@@ -17,7 +17,7 @@ export function Canvas({
   selectedColor, 
   canvasWidth, 
   canvasHeight, 
-  showGrid, 
+
   onPixelClick,
   cooldownActive 
 }: CanvasProps) {
@@ -68,7 +68,7 @@ export function Canvas({
         data-testid="canvas-container"
       >
         <div 
-          className={cn("grid mx-auto border border-gray-400 relative", showGrid && "grid-lines")}
+          className="grid mx-auto border border-gray-400 relative"
           style={canvasStyle}
           data-testid="pixel-canvas"
         >