Initial setup: Korean community aggregator web app

- Set up Vite + React + TypeScript project
- Configure Tailwind CSS v4 with PostCSS
- Create project structure (components, types, data)
- Implement core features:
  - Header with search functionality
  - PostCard component for displaying posts
  - PostList with community filtering (전체/디씨/루리웹/아카)
  - PostModal for detailed post view
- Add mock data for 3 communities (DCInside, Ruliweb, Arcalive)
- Update README with project documentation

tsconfig.json

@@ -0,0 +1,7 @@
+{
+  "files": [],
+  "references": [
+    { "path": "./tsconfig.app.json" },
+    { "path": "./tsconfig.node.json" }
+  ]
+}