feat: Add Docker-based validator setup

- Created Dockerfile with multi-stage build
- Added docker-compose.yml with validator service
- Integrated Prometheus and Grafana monitoring (optional)
- Health checks and automatic restarts
- Volume management for data persistence
- Comprehensive Docker README with troubleshooting
- Updated main README with Docker instructions

Docker setup features:
- One-command deployment
- Auto-restart on failure
- Built-in monitoring stack
- Production-ready configuration
- Easy backup and restore

docker/docker-compose.yml

@@ -0,0 +1,82 @@
+version: '3.8'
+
+services:
+  pezkuwi-validator:
+    build:
+      context: .
+      dockerfile: Dockerfile
+    container_name: pezkuwi-validator
+    restart: unless-stopped
+    ports:
+      - "30333:30333"  # P2P
+      - "9944:9944"    # RPC
+      - "9615:9615"    # Prometheus metrics
+    volumes:
+      - validator-data:/pezkuwi/data
+      - ./chain-spec.json:/pezkuwi/chain-spec.json:ro
+    environment:
+      - RUST_LOG=info
+    command: [
+      "--chain", "/pezkuwi/chain-spec.json",
+      "--base-path", "/pezkuwi/data",
+      "--validator",
+      "--name", "Docker-Validator",
+      "--port", "30333",
+      "--rpc-port", "9944",
+      "--rpc-cors", "all",
+      "--rpc-external",
+      "--rpc-methods=unsafe",
+      "--prometheus-external",
+      "--prometheus-port", "9615"
+    ]
+    networks:
+      - pezkuwi-network
+    logging:
+      driver: "json-file"
+      options:
+        max-size: "10m"
+        max-file: "3"
+
+  # Optional: Prometheus monitoring
+  prometheus:
+    image: prom/prometheus:latest
+    container_name: pezkuwi-prometheus
+    restart: unless-stopped
+    ports:
+      - "9090:9090"
+    volumes:
+      - ./prometheus.yml:/etc/prometheus/prometheus.yml:ro
+      - prometheus-data:/prometheus
+    command:
+      - '--config.file=/etc/prometheus/prometheus.yml'
+      - '--storage.tsdb.path=/prometheus'
+    networks:
+      - pezkuwi-network
+    profiles:
+      - monitoring
+
+  # Optional: Grafana dashboard
+  grafana:
+    image: grafana/grafana:latest
+    container_name: pezkuwi-grafana
+    restart: unless-stopped
+    ports:
+      - "3000:3000"
+    volumes:
+      - grafana-data:/var/lib/grafana
+    environment:
+      - GF_SECURITY_ADMIN_PASSWORD=pezkuwi123
+      - GF_USERS_ALLOW_SIGN_UP=false
+    networks:
+      - pezkuwi-network
+    profiles:
+      - monitoring
+
+volumes:
+  validator-data:
+  prometheus-data:
+  grafana-data:
+
+networks:
+  pezkuwi-network:
+    driver: bridge