Add production deployment config, Alembic migration, switch to Haiku

- Production Docker Compose with Caddy reverse proxy, Gunicorn, Nginx
- Multi-stage frontend build for production
- Deploy script and automated database backup script
- Initial Alembic migration with all tables
- Switch recommendation model from Sonnet to Haiku for cost efficiency

backup.sh

@@ -0,0 +1,20 @@
+#!/bin/bash
+set -e
+
+# Vynl database backup script
+# Run via cron: 0 3 * * * /path/to/backup.sh
+
+BACKUP_DIR="/backups/vynl"
+TIMESTAMP=$(date +%Y%m%d_%H%M%S)
+KEEP_DAYS=14
+
+mkdir -p "$BACKUP_DIR"
+
+# Dump database from running container
+docker compose -f docker-compose.prod.yml exec -T db \
+    pg_dump -U vynl vynl | gzip > "${BACKUP_DIR}/vynl_${TIMESTAMP}.sql.gz"
+
+# Remove backups older than KEEP_DAYS
+find "$BACKUP_DIR" -name "vynl_*.sql.gz" -mtime +${KEEP_DAYS} -delete
+
+echo "Backup complete: vynl_${TIMESTAMP}.sql.gz"