fix(k3s): reject HTML responses and extend CAPTCHA expiration

flux/infrastructure/infra-net/helmrelease-ingress-nginx.yaml

@@ -156,6 +156,8 @@ spec:
               value: "10"
             - name: REQUEST_TIMEOUT
               value: "1000"
+            - name: CAPTCHA_EXPIRATION
+              value: "14400"
             - name: CAPTCHA_PROVIDER
               value: "turnstile"
             - name: SITE_KEY