bedrock: Always use 1M context window for anthropic models (#56195)

Closes #49617

Release Notes:

- bedrock: Always use 1M context windows for Anthropic models
b3c65f9410Bennet Bo Fenner committed on 5/8/2026, 3:43:52 PM· committed by GitHubparent392961e
6 files changedLine totals unavailable