feat: initial full-stack nyaa-crawler implementation

- Node.js + TypeScript + Express backend using built-in node:sqlite
- React + Vite frontend with dark-themed UI
- Nyaa.si RSS polling via fast-xml-parser
- Watch list with show/episode CRUD and status tracking
- Auto-download scheduler with node-cron (configurable interval)
- .torrent file downloader with batch-release filtering
- Settings page for poll interval and quality defaults
- Dockerfile and docker-compose for Unraid deployment
- SQLite DB with migrations (shows, episodes, settings tables)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

.claude/settings.local.json

@@ -0,0 +1,8 @@
+{
+  "permissions": {
+    "allow": [
+      "Bash(npm install:*)",
+      "Bash(npx tsc:*)"
+    ]
+  }
+}