* fix: Token Spending Logic for Multi-Agents on Abort Scenarios
* Implemented logic to skip token spending if a conversation is aborted, preventing double-spending.
* Introduced `spendCollectedUsage` function to handle token spending for multiple models during aborts, ensuring accurate accounting for parallel agents.
* Updated `GenerationJobManager` to store and retrieve collected usage data for improved abort handling.
* Added comprehensive tests for the new functionality, covering various scenarios including cache token handling and parallel agent usage.
* fix: Memory Context Handling for Multi-Agents
* Refactored `buildMessages` method to pass memory context to parallel agents, ensuring they share the same user context.
* Improved handling of memory context when no existing instructions are present for parallel agents.
* Added comprehensive tests to verify memory context propagation and behavior under various scenarios, including cases with no memory available and empty agent configurations.
* Enhanced logging for better traceability of memory context additions to agents.
* chore: Memory Context Documentation for Parallel Agents
* Updated documentation in the `AgentClient` class to clarify the in-place mutation of agentConfig objects when passing memory context to parallel agents.
* Added notes on the implications of mutating objects directly to ensure all parallel agents receive the correct memory context before execution.
* chore: UsageMetadata Interface docs for Token Spending
* Expanded the UsageMetadata interface to support both OpenAI and Anthropic cache token formats.
* Added detailed documentation for cache token properties, including mutually exclusive fields for different model types.
* Improved clarity on how to access cache token details for accurate token spending tracking.
* fix: Enhance Token Spending Logic in Abort Middleware
* Refactored `spendCollectedUsage` function to utilize Promise.all for concurrent token spending, improving performance and ensuring all operations complete before clearing the collectedUsage array.
* Added documentation to clarify the importance of clearing the collectedUsage array to prevent double-spending in abort scenarios.
* Updated tests to verify the correct behavior of the spending logic and the clearing of the array after spending operations.
