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>

src/server/config.ts

@@ -0,0 +1,8 @@
+import 'dotenv/config';
+
+export const config = {
+  port: parseInt(process.env.PORT || '3000', 10),
+  host: process.env.HOST || '0.0.0.0',
+  databasePath: process.env.DATABASE_PATH || './data/pricehunter.db',
+  isProduction: process.env.NODE_ENV === 'production',
+};