[breaking] Azure AI Foundry retires gpt-4.1, gpt-4.1-mini, gpt-4.1-nano on 2026-10-14

Azure AI Foundry lists gpt-4.1 (2025-04-14), gpt-4.1-mini (2025-04-14), gpt-4.1-nano (2025-04-14) as deprecated with retirement on 2026-10-14. Azure retirement dates are platform-specific and may differ from the model provider's own schedule. The page does not date the announcements; announced_at reflects the page capture date. Effective: 2026-10-14. Affected: microsoft/gpt-4.1-2025-04-14, microsoft/gpt-4.1-mini-2025-04-14, microsoft/gpt-4.1-nano-2025-04-14. Severity: breaking. Verification: verified.