fix(k8s): repair-known-hosts secret optional:true — Pod 不阻塞等待 secret 建立

CD 首次跑時才建立 secret，optional 讓 Pod 先起來
等 CD 建立 secret 後自動掛載

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

k8s/awoooi-prod/06-deployment-api.yaml

@@ -109,9 +109,11 @@ spec:
             secretName: awoooi-repair-ssh-key
             defaultMode: 0400  # 八進位 0400 = 十進位 256 = r-------- (owner read-only)
         # 2026-04-06 Claude Code: Sprint 3 Security Fix A1
+        # optional: true — CD 首次跑時建立 secret，Pod 不阻塞等待
         - name: repair-known-hosts
           secret:
             secretName: awoooi-repair-known-hosts
+            optional: true
 
 ---
 apiVersion: v1