AWS Bedrock anthropic.claude-sonnet-4-20250514-v1:0: deprecated → retiring

AWS Bedrock anthropic.claude-sonnet-4-20250514-v1:0 (bedrock/anthropic.claude-sonnet-4-20250514-v1-0) is now retiring, previously deprecated. Scheduled retirement: 2026-10-14. Verified against the provider's own published schedule.