docs(README): format code blocks for SSH key generation instructions

flux/README.md

@@ -32,6 +32,29 @@ flux/
 └── apps/                                # Halo, RustDesk, Whoami, 证书, Ingress
 ```
 
+## 前置准备
+
+需要提前生成git访问凭证
+
+```shell
+ssh-keygen -t ed25519 -C "flux" -f ./flux-git-auth -N ""
+
+ssh-keyscan github.com > ./known_hosts
+
+kubectl -n infra-gitops create secret generic flux-git-auth \
+ --from-file=identity=./flux-git-auth \
+ --from-file=identity.pub=./flux-git-auth.pub \
+ --from-file=known_hosts=./known_hosts
+```
+
+然后将 `flux-git-auth.pub` 文件内容添加到远端仓库中
+
+应用flux实例 后续将自动开启部署流程
+
+```shell
+kubectl apply -f flux/flux-instance.yaml
+```
+
 ## 部署顺序
 
 ```