fix: replace img tags with next/image, fix useEffect deps, suppress test mock warnings

- projects/page.tsx & projects/[slug]/page.tsx: <img> → <Image fill unoptimized>
- ActivityFeed.tsx: add allQuotes.length to useEffect deps
- Test mocks: eslint-disable for intentional <img> in next/image mocks

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

app/projects/[slug]/page.tsx

@@ -2,6 +2,7 @@
 
 import { motion } from 'framer-motion';
 import { ExternalLink, Calendar, ArrowLeft, Github as GithubIcon, Share2 } from 'lucide-react';
+import Image from 'next/image';
 import Link from 'next/link';
 import { useParams } from 'next/navigation';
 import { useState, useEffect } from 'react';
@@ -132,9 +133,11 @@ const ProjectDetail = () => {
             className="mb-16 rounded-2xl overflow-hidden shadow-2xl bg-stone-100 aspect-video relative"
         >
              {project.imageUrl ? (
-                <img 
+                <Image 
                     src={project.imageUrl} 
                     alt={project.title} 
+                    fill
+                    unoptimized
                     className="w-full h-full object-cover"
                 />
              ) : (