[cross-repo] Integrate Homestead Foundry with Project 42 content maintenance

[hcs-platform-app]

Projected from ADO Feature #5771 (Project 42). This issue is bot-managed — edits here are not reflected back to ADO and will be reverted.

Project 42's learning and Field Guide content can become stale quickly as AI models, products, interfaces, and practices change. Homestead Foundry should provide the agents and deployed-model orchestration that monitor those changes and prepare governed updates.

Why now: New capabilities such as Google's Gemini Spark demonstrate that significant AI changes can arrive faster than a manual editorial process can reliably track.

In scope:

• Use Homestead Foundry agents and approved deployed models to monitor primary sources for Anthropic, OpenAI, Google, and provider-neutral AI topics.
• Map detected changes to affected Learn modules, checks, scripts, Field Guide resources, and visual guides.
• Generate evidence-linked content proposals, tests, impact reports, and draft pull requests.
• Require human editorial approval before merge or publication.
• Record model routing, prompts, evidence, evaluations, cost, audit history, and rollback.

Out of scope:

• Autonomous publication to production.
• Replacing subject-matter review with model confidence.
• Using Homestead Foundry as the public Project 42 web host.
• The deferred virtual-instructor runtime.