Initial commit: Price Hunter — self-hosted price comparison engine

Complete application scaffolding with:
- Backend: Node.js + Fastify + sql.js (SQLite)
- Frontend: SvelteKit + Tailwind CSS
- Scraper engine with parallel fan-out, rate limiting, cheerio-based parsing
- Store management with CSS selector config and per-store test pages
- Docker setup for single-command deployment

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

docker-compose.yml

@@ -0,0 +1,12 @@
+services:
+  pricehunter:
+    build: .
+    ports:
+      - "${PORT:-3000}:3000"
+    volumes:
+      - ./data:/app/data
+    environment:
+      - NODE_ENV=production
+      - DATABASE_PATH=/app/data/pricehunter.db
+      - PORT=3000
+    restart: unless-stopped