feat: implement MC domain filter proxy, API, dashboard

- proxy: asyncio TCP proxy with handshake parser, domain whitelist,
  transparent backend tunneling, SQLite logging, mtime hot reload
- api: FastAPI routes for config/domains/logs/status + restart trigger
- frontend: React + Vite NPM-style dashboard (dashboard/domains/logs/settings)
- nginx: reverse proxy for /api -> api:8000 and / -> frontend:3000
- docker-compose: full stack with shared data volume
- replace spec mc-domain-filter.md with README.md

frontend/package.json

@@ -0,0 +1,20 @@
+{
+  "name": "mc-domain-filter-frontend",
+  "version": "0.1.0",
+  "private": true,
+  "type": "module",
+  "scripts": {
+    "dev": "vite",
+    "build": "vite build",
+    "preview": "vite preview --host 0.0.0.0 --port 3000"
+  },
+  "dependencies": {
+    "react": "^18.3.1",
+    "react-dom": "^18.3.1",
+    "react-router-dom": "^6.26.2"
+  },
+  "devDependencies": {
+    "@vitejs/plugin-react": "^4.3.1",
+    "vite": "^5.4.6"
+  }
+}