feat: add Kubernetes deployment support

[nillikechatchat]

Summary

• Add Kustomize-based K8s deployment files
• Support all HiClaw components: MinIO, Matrix (Tuwunel), Higress, Element Web, Manager
• Include Ingress configuration for external access
• Add one-click deployment script
• Add detailed deployment tutorial in Chinese

Motivation

This addresses issue #245 - community request for K8s deployment mode support.

Files Changed

deploy/k8s/
├── README.md           # K8s deployment guide
├── kustomization.yaml  # Kustomize config
├── namespace.yaml      # Namespace definition
├── secrets.yaml        # Secrets template
├── minio.yaml          # MinIO file storage
├── matrix.yaml         # Matrix (Tuwunel) IM server
├── higress.yaml        # Higress AI Gateway
├── element.yaml        # Element Web frontend
├── manager.yaml        # HiClaw Manager
├── ingress.yaml        # Ingress routes
└── deploy.sh           # One-click deployment script

docs/zh-cn/deployment/
└── hiclaw-k8s-deployment-tutorial.md  # Detailed tutorial

Usage

# 1. Configure secrets
vim deploy/k8s/secrets.yaml

# 2. Deploy
kubectl apply -k deploy/k8s/

Test Plan

• Test on minikube
• Test on cloud K8s (ACK, EKS, GKE)
• Verify all components start correctly
• Verify inter-service communication
• Verify external access via Ingress

Closes #245