feat(api): implement user authentication and registration endpoints

- Add main application logic in `api/src/main.rs` to initialize server, database, and services.
- Create authentication routes in `api/src/routes/auth.rs` for login, register, logout, and user info retrieval.
- Implement configuration route in `api/src/routes/config.rs` to expose application settings.
- Define application state management in `api/src/state.rs` to share user service and configuration.
- Set up Docker Compose configuration in `compose.yml` for backend, worker, and database services.
- Establish domain logic in `domain` crate with user entities, repositories, and services.
- Implement SQLite user repository in `infra/src/user_repository.rs` for user data persistence.
- Create database migration handling in `infra/src/db.rs` and session store in `infra/src/session_store.rs`.
- Add necessary dependencies and features in `Cargo.toml` files for both `domain` and `infra` crates.

compose.yml

@@ -0,0 +1,50 @@
+services:
+  backend:
+    build: .
+    ports:
+      - "3000:3000"
+    environment:
+      # In production, use a secure secret
+      - SESSION_SECRET=dev_secret_key_12345
+      - DATABASE_URL=sqlite:///app/data/notes.db
+      - CORS_ALLOWED_ORIGINS=http://localhost:8080,http://localhost:5173
+      - HOST=0.0.0.0
+      - PORT=3000
+    volumes:
+      - ./data:/app/data
+
+  worker:
+    build: .
+    command: ["./notes-worker"]
+    environment:
+      - DATABASE_URL=sqlite:///app/data/notes.db
+      - BROKER_URL=nats://nats:4222
+      - QDRANT_URL=http://qdrant:6334
+      - EMBEDDING_PROVIDER=fastembed
+    depends_on:
+      - backend
+      - nats
+      - qdrant
+    volumes:
+      - ./data:/app/data
+
+  nats:
+    image: nats:alpine
+    ports:
+      - "4222:4222"
+      - "6222:6222"
+      - "8222:8222"
+    restart: unless-stopped
+  db:
+    image: postgres:15-alpine
+    environment:
+      POSTGRES_USER: user
+      POSTGRES_PASSWORD: password
+      POSTGRES_DB: k_template_db
+    ports:
+      - "5432:5432"
+    volumes:
+      - db_data:/var/lib/postgresql/data
+
+volumes:
+  db_data: