Adds Docker setup and basic API endpoints

WHAT: Introduces Dockerfiles for development and production, Docker Compose configurations, a Makefile for common tasks, shell scripts for environment setup/teardown, a basic Express API with SQLite integration.
WHY: Enables easy setup and deployment of the application using Docker. Provides basic API endpoints for managing purchase items.
HOW:
- Creates `docker-compose.dev.yml` and `docker-compose.prod.yml` to define services and volumes.
- Introduces `Dockerfile.dev` and `Dockerfile.prod` to build container images with necessary dependencies.
- Adds `Makefile` with commands for building, running, and managing the application.
- Implements shell scripts for simplified Docker environment management.
- Sets up Express API with endpoints for CRUD operations on purchase items, using SQLite as the database.
- Uses `better-sqlite3` to connect and interact with the SQLite database.

docker/docker-compose.prod.yml

@@ -0,0 +1,19 @@
+services:
+  api:
+    build:
+      context: ..
+      dockerfile: docker/Dockerfile.prod
+    image: dm-purchase-api:prod
+    platform: linux/amd64
+    ports:
+      - "8080:8080"
+    environment:
+      - DB_PATH=/data/purchase.db
+    volumes:
+      - dm_db:/data
+    restart: unless-stopped
+
+volumes:
+  dm_db:
+
+