feat: 新增以稿写稿和文章融合功能

- 新增以稿写稿 (MimicWriter) 功能：支持分析文章风格并仿写，包含风格分析、逐段仿写等模式
- 新增文章融合 (ArticleFusion) 功能：支持智能分析两篇文章优劣并生成融合版本
- 新增后端 API 服务器 (Express + SQLite) 用于范式管理
- 更新 .gitignore 忽略运行时数据文件 (data/, *.db)

Co-Authored-By: Claude <noreply@anthropic.com>

package.json

@@ -5,7 +5,9 @@
   "scripts": {
     "dev": "vite",
     "build": "vite build",
-    "preview": "vite preview"
+    "preview": "vite preview",
+    "server": "node server/index.js",
+    "start": "concurrently \"npm run server\" \"npm run dev\""
   },
   "dependencies": {
     "@tailwindcss/vite": "^4.1.18",
@@ -14,8 +16,11 @@
     "@tiptap/starter-kit": "^3.15.3",
     "@tiptap/vue-3": "^3.15.3",
     "axios": "^1.6.0",
+    "better-sqlite3": "^11.0.0",
+    "cors": "^2.8.5",
     "diff-match-patch": "^1.0.5",
     "docx": "^9.5.1",
+    "express": "^4.18.2",
     "file-saver": "^2.0.5",
     "marked": "^9.1.0",
     "pinia": "^2.1.0",
@@ -26,10 +31,11 @@
     "@tailwindcss/postcss": "^4.1.18",
     "@vitejs/plugin-vue": "^4.5.0",
     "autoprefixer": "^10.4.23",
+    "concurrently": "^8.2.0",
     "dotenv": "^16.3.1",
     "playwright": "^1.57.0",
     "postcss": "^8.5.6",
     "tailwindcss": "^4.1.18",
     "vite": "^5.0.0"
   }
-}
+}