Add flex-auth protected-system tutorial (NK-WP-0009-T05)

Offline steps exercised against the secrets-engine example; live caller-auth steps remain unexercised. Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com> Assistant: claude-code Assistant-Model: sonnet Assistant-Process: 295952@bnt-lap001 Assistant-Session: e93f64ad-516c-46eb-9666-aad8d300c477
2026-09-28 23:44:44 +02:00 · 2026-09-28 23:44:44 +02:00 · 923e211365
commit 923e211365
parent 2a004a70ea
3 changed files with 127 additions and 3 deletions
--- a/workplans/NK-WP-0009-netkingdom-security-pattern-tutorials.md
+++ b/workplans/NK-WP-0009-netkingdom-security-pattern-tutorials.md
@ -122,7 +122,7 @@ implementation.

 ```task
 id: NK-WP-0009-T05
-status: todo
+status: progress
 priority: medium
 state_hub_task_id: "c380ef19-4bc2-5ade-b127-baf18c64bf35"
 ```