docs: add AGENTS.md (AI-contributor guardrails) + AGENTS_USER_EXAMPLE.md#343

MichaelLeeHobbs wants to merge 2 commits into

OpenIntegrationEngine:mainOpenIntegrationEngine/engine:mainfrom

MichaelLeeHobbs:feature/claude-md-ai-guidanceMichaelLeeHobbs/engine:feature/claude-md-ai-guidanceCopy head branch name to clipboard