feat: 添加ConfigMap管理配置，密码使用Secret

k8s/secret.yaml

@@ -1,5 +1,15 @@
 apiVersion: v1
 kind: Secret
+metadata:
+  name: todo-backend-secret
+  namespace: drone
+type: Opaque
+data:
+  # 密码需要base64编码，例如 echo -n 'your_password' | base64
+  SPRING_DATASOURCE_PASSWORD: cG9zdGdyZXM=  # postgres
+---
+apiVersion: v1
+kind: Secret
 metadata:
   name: tencentyun-secret
   namespace: drone