main:新增 Kubernetes 部署配置及文档

变更内容：
- 添加 Kubernetes 部署配置文件，包括 API Deployment、Worker Deployment 和 Redis Deployment。
- 新增 Service 定义，支持 API、Metrics 和 Redis 的集群访问。
- 配置 ConfigMap，用于全局共享环境变量。
- 编写 Kubernetes 部署指南文档，包含快速部署步骤、建议配置及故障排查方法。
- 提升系统的可扩展性和容器编排能力，适配生产环境使用。

deployment/kubernetes/service.yaml

@@ -1,9 +1,15 @@
+# Kubernetes Service 配置
+# 包含：API Service、Metrics Service、Redis Service
+
+---
+# API Service - 对外暴露 HTTP 服务
 apiVersion: v1
 kind: Service
 metadata:
-  name: functional-scaffold
+  name: functional-scaffold-api
   labels:
     app: functional-scaffold
+    component: api
 spec:
   type: ClusterIP
   ports:
@@ -13,13 +19,21 @@ spec:
     name: http
   selector:
     app: functional-scaffold
+    component: api
+
 ---
+# Metrics Service - Prometheus 抓取指标
 apiVersion: v1
 kind: Service
 metadata:
   name: functional-scaffold-metrics
   labels:
     app: functional-scaffold
+    component: api
+  annotations:
+    prometheus.io/scrape: "true"
+    prometheus.io/port: "8000"
+    prometheus.io/path: "/metrics"
 spec:
   type: ClusterIP
   ports:
@@ -29,3 +43,24 @@ spec:
     name: metrics
   selector:
     app: functional-scaffold
+    component: api
+
+---
+# Redis Service - 内部 Redis 服务
+apiVersion: v1
+kind: Service
+metadata:
+  name: functional-scaffold-redis
+  labels:
+    app: functional-scaffold
+    component: redis
+spec:
+  type: ClusterIP
+  ports:
+  - port: 6379
+    targetPort: 6379
+    protocol: TCP
+    name: redis
+  selector:
+    app: functional-scaffold
+    component: redis