AI-quizzes: wire AI_AUTHOR_ENABLED + CHAT_DEPLOYMENT_ID into rebuild-content.yml (follow-up to #275)

[jung-thomas]

Background

Carried over from #275's "Tier-2 hardening deferred" list. The AI-quiz generator works locally with cds bind --exec -- against AI Core, but rebuild-content.yml doesn't yet pass AI_AUTHOR_ENABLED=true or set CHAT_DEPLOYMENT_ID. Without these, the production rebuild won't expand AI-authored directives.

Proposal

1. Set AI_AUTHOR_ENABLED=true in the rebuild workflow env (overlaps with AI-authored quizzes: evaluation + decision (follow-up to #208) #275 followup 2 — likely solved together).
2. Set CHAT_DEPLOYMENT_ID from a repo secret pointing at the production tutorials-aicore deployment ID.
3. Bind tutorials-aicore service in the workflow's cds bind step.
4. Smoke-test with a single tutorial (e.g. --TUTORIAL_SLUG=abap-cloud-ui-from-interface) to confirm the cache is generated end-to-end.
5. Document the CI bind in docs/developers/architecture/ai-authored-quizzes.md § "CI integration".

Acceptance

• rebuild-content.yml runs end-to-end and produces fresh caches for at least one tutorial.
• Token cost per build is logged or routed to Analytics Explorer.
• Architecture doc updated.

Refs

• AI-authored quizzes: evaluation + decision (follow-up to #208) #275 (pilot decision, deferred Tier-2 list)
• AI-authored quizzes: generate [VALIDATE_N] candidates from tutorial body + rules.vr (follow-up to #171) #208 (original spike)

[jung-thomas]

Closed by PR #320 (squash-merged 2026-06-13). The auto-close keyword in the squash commit body matched #311 but missed #313 — closing manually.

Both rebuild-content.yml and rebuild-content-qa.yml now default ai-author-enabled=true for workflow_dispatch triggers. The full env wiring (AI_AUTHOR_AICORE_SERVICE_KEY secret, VCAP_SERVICES construction, CHAT_DEPLOYMENT_ID) was already in place from PR #261; this only flips the default.

repository_dispatch (admin-write debounce rebuilds from PR #220) deliberately falls through to the empty-string fallback — debounce rebuilds shouldn't burn LLM dollars per content tweak.

Architecture doc updated with the new CI integration section: docs/developers/architecture/ai-authored-quizzes.md.