Add crawler implementation (Node.js + TypeScript)

- Create crawler project structure
- Implement base crawler class with safety features
- Add crawlers for Ruliweb, Arcalive, DCInside
- Implement utilities: fetcher (with retry logic), logger
- Configure crawling settings (3s delay, max 20 posts/board)
- Add test script and scheduler (30min intervals)

Safety measures:
- 3 second delay between requests
- Exponential backoff retry logic
- Respect robots.txt (DCInside disabled)
- User-Agent and proper headers

Current status:
- Structure complete
- Both Ruliweb and Arcalive return 403 (bot detection)
- Need to decide: Puppeteer, switch targets, or use mock data

crawler/package.json

@@ -0,0 +1,27 @@
+{
+  "name": "community-crawler",
+  "version": "1.0.0",
+  "description": "Korean community crawler",
+  "main": "dist/index.js",
+  "type": "module",
+  "scripts": {
+    "dev": "tsx watch src/index.ts",
+    "build": "tsc",
+    "start": "node dist/index.js",
+    "test": "tsx src/test.ts"
+  },
+  "keywords": ["crawler", "community", "korea"],
+  "author": "",
+  "license": "MIT",
+  "dependencies": {
+    "axios": "^1.7.9",
+    "cheerio": "^1.0.0",
+    "node-cron": "^3.0.3"
+  },
+  "devDependencies": {
+    "@types/node": "^22.10.2",
+    "@types/node-cron": "^3.0.11",
+    "tsx": "^4.19.2",
+    "typescript": "^5.7.2"
+  }
+}