## What changed
- Switch Amazon Bedrock remote compaction to `compaction_trigger` items sent through `/v1/responses`.
- Remove the legacy dedicated compaction protocol from provider capabilities.
- Default remote compaction to unsupported and explicitly enable it for OpenAI, Azure Responses, and Amazon Bedrock providers.
## Testing
- Cover manual and automatic Amazon Bedrock compaction requests and their compacted history.
- Verify remote-compaction capabilities for configured and Amazon Bedrock providers.
GitOrigin-RevId: cf9ba314595367518b37a85f334f0c105ce47e45