feat: Complete multi-blog setup with 12 collections and subdomain routing

- Added 12 blog collections: art, bfs, dfs, problems, puzzles, reviews, reflections, vibes, workflows, magic, contests, poetry
- Created content config with glob loaders for all collections
- Added sample posts for each collection
- Fixed TypeScript collection recognition by removing duplicate config
- Made BlogPosts component collection-aware for proper routing
- Created individual post pages ([...slug].astro) for each collection
- Added Netlify subdomain routing configuration
- Updated all references to use neeldhara.blog as main domain
- Fixed navigation links in all-blogs component

Ready for GitHub/Netlify deployment with subdomain support.

src/pages/puzzles/index.astro

@@ -0,0 +1,24 @@
+---
+import { getCollection } from 'astro:content';
+import DefaultLayout from '@/layouts/DefaultLayout.astro';
+import { BlogPosts } from '@/components/sections/blog-posts';
+
+const posts = (await getCollection('puzzles')).sort(
+	(a, b) => b.data.pubDate.valueOf() - a.data.pubDate.valueOf(),
+);
+
+const SITE_TITLE = 'Puzzles - Logic, Mathematics, and Interactive Challenges';
+const SITE_DESCRIPTION = 'Mathematical puzzles, logic problems, and interactive challenges that teach algorithmic thinking.';
+---
+
+<DefaultLayout title={SITE_TITLE} description={SITE_DESCRIPTION}>
+	<div class="py-16 md:py-28 lg:py-32">
+		<div class="container max-w-5xl">
+			<div class="mb-12">
+				<h1 class="text-4xl font-bold mb-4">Puzzles</h1>
+				<p class="text-xl text-muted-foreground">{SITE_DESCRIPTION}</p>
+			</div>
+			<BlogPosts posts={posts} collection="puzzles" client:only='react' />
+		</div>
+	</div>
+</DefaultLayout>