feat: implement WYSIWYG markdown editor with Go backend and React frontend

- Backend: Go HTTP server with Cobra CLI (--data-dir, --port, --host flags)
- CRUD REST API for markdown files with JSON error responses
- File storage in flat directory structure (flat structure, .md files only)
- Comprehensive logrus logging for all operations
- Static file serving for frontend build (./frontend/dist)
- Frontend: React + TypeScript + Tailwind CSS
- Markdown editor with live GFM preview
- File management: list, create, open, save, delete
- Theme system (Dark, Light, System) with persistence
- Responsive design for desktop and mobile
- Backend tests (storage, API handlers) and frontend tests

frontend/package.json

@@ -0,0 +1,29 @@
+{
+  "name": "eval-frontend",
+  "version": "0.1.0",
+  "private": true,
+  "type": "module",
+  "scripts": {
+    "dev": "vite",
+    "build": "tsc && vite build",
+    "preview": "vite preview",
+    "test": "vitest"
+  },
+  "dependencies": {
+    "react": "^19.0.0",
+    "react-dom": "^19.0.0",
+    "react-markdown": "^9.0.0",
+    "remark-gfm": "^4.0.0"
+  },
+  "devDependencies": {
+    "@types/react": "^19.0.0",
+    "@types/react-dom": "^19.0.0",
+    "@vitejs/plugin-react": "^4.3.0",
+    "autoprefixer": "^10.4.20",
+    "postcss": "^8.4.47",
+    "tailwindcss": "^3.4.11",
+    "typescript": "^5.6.0",
+    "vite": "^5.4.0",
+    "vitest": "^2.1.0"
+  }
+}