fix: resolve ESLint warning and silence test console output

- Replace <img> with Next.js <Image> in not-found.tsx
- Add console mock in jest.setup.js to silence logs during tests

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

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

app/not-found.tsx

@@ -1,6 +1,7 @@
 "use client";
 
 import Link from "next/link";
+import Image from "next/image";
 import { useRouter } from "next/navigation";
 
 export default function NotFound() {
@@ -12,10 +13,13 @@ export default function NotFound() {
         {/* Logo and 404 */}
         <div className="mb-8">
           <div className="flex justify-center mb-8">
-            <img
+            <Image
               src="/logos/logo.svg"
               alt="Thé Tip Top Logo"
+              width={320}
+              height={100}
               className="w-64 h-auto md:w-80"
+              priority
             />
           </div>
           <div className="text-[120px] md:text-[150px] leading-none font-bold text-[#d4a574] opacity-30 select-none">

jest.setup.js

@@ -1,6 +1,20 @@
 // Learn more: https://github.com/testing-library/jest-dom
 import '@testing-library/jest-dom';
 
+// Silence console output during tests
+const originalConsole = { ...console };
+beforeAll(() => {
+  jest.spyOn(console, 'log').mockImplementation(() => {});
+  jest.spyOn(console, 'warn').mockImplementation(() => {});
+  jest.spyOn(console, 'error').mockImplementation(() => {});
+});
+
+afterAll(() => {
+  console.log = originalConsole.log;
+  console.warn = originalConsole.warn;
+  console.error = originalConsole.error;
+});
+
 // Mock Next.js router
 jest.mock('next/navigation', () => ({
   useRouter() {