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.

astro.config.mjs

@@ -0,0 +1,20 @@
+// @ts-check
+import { defineConfig } from "astro/config";
+import mdx from "@astrojs/mdx";
+import sitemap from "@astrojs/sitemap";
+
+import react from "@astrojs/react";
+// @ts-ignore - TailwindCSS v4 Vite plugin has type compatibility issues with Astro
+import tailwindcss from "@tailwindcss/vite";
+
+// https://astro.build/config
+export default defineConfig({
+  site: "https://neeldhara.blog",
+  integrations: [mdx(), sitemap(), react()],
+  output: "static",
+
+  vite: {
+    // @ts-ignore - Suppress TypeScript error for TailwindCSS v4 plugin compatibility
+    plugins: [tailwindcss()],
+  },
+});