feat: add modelConfig recipe

[seanryankeegan]

Summary

• Adds the modelConfig recipe to 04_architecturalPatterns, demonstrating how to use model_config in Agent Script to assign different AI models at the agent level and per subagent
• Shows the model inheritance hierarchy: subagent override > agent default > org default
• Covers three practical use cases: EinsteinHyperClassifier for fast routing, cost-efficient default (GPT-4o Mini) for high-volume FAQ, Trust Boundary compliance (Claude Haiku 4.5 on Bedrock) for billing, and deep reasoning (Claude Opus 4.5 on Bedrock) for technical support

Test plan

• Deploy to a scratch org: sf project deploy start --source-dir force-app/main/04_architecturalPatterns/modelConfig
• Open agent in Agentforce Builder and verify 0 errors / 0 warnings in the Problems panel
• Test routing: "What are your store hours?" → routes to general_faq
• Test routing: "I was charged twice for my order" → routes to billing_inquiry
• Test routing: "My API integration fails with a 401 after rotating keys" → routes to technical_support
• Confirm correct subagent transitions in Agent Tracer

cc @msrivastava13 for review

[github-actions]

Salesforce Code Analyzer found 82 violations, including 0 in files changed by this pull request. See job summary page.

[seanryankeegan]

@msrivastava13 — flagging the scratch-org-test CI failure. The error is:

You attempted to deploy 52 instances of AiAuthoringBundle, more than the maximum limit of 50 allowed by the system.

The CI scratch org has hit the 50 AiAuthoringBundle limit — not related to this recipe. Looks like a CI environment issue that needs a fresh scratch org or a cleanup. The recipe itself deploys and validates fine locally.