* 🔄 fix: Include usage in stream options for OpenAI and Azure endpoints
* fix: Agents support for Azure serverless endpoints
* fix: Refactor condition for assistants and azureAssistants endpoint handling
* AWS Titan via Bedrock: model doesn't support system messages, Closes#6456
* fix: Add EndpointSchemaKey type to endpoint parameters in buildDefaultConvo and ensure assistantId is always defined
* fix: Handle new conversation state for assistants endpoint in finalHandler
* fix: Add spec and iconURL parameters to `saveAssistantMessage` to persist modelSpec fields
* fix: Handle assistant unlinking even if no valid files to delete
* chore: move type definitions from callbacks.js to typedefs.js
* chore: Add StandardGraph typedef to typedefs.js
* chore: Update parameter type for graph in ModelEndHandler to StandardGraph
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Co-authored-by: Andres Restrepo <andres@enric.ai>