* feat: Add LLM call events for improved observability
- Introduce new LLM call events: LLMCallStartedEvent, LLMCallCompletedEvent, and LLMCallFailedEvent
- Emit events for LLM calls and tool calls to provide better tracking and debugging
- Add event handling in the LLM class to track call lifecycle
- Update event bus to support new LLM-related events
- Add test cases to validate LLM event emissions
* feat: Add event handling for LLM call lifecycle events
- Implement event listeners for LLM call events in EventListener
- Add logging for LLM call start, completion, and failure events
- Import and register new LLM-specific event types
* less log
* refactor: Update LLM event response type to support Any
* refactor: Simplify LLM call completed event emission
Remove unnecessary LLMCallType conversion when emitting LLMCallCompletedEvent
* refactor: Update LLM event docstrings for clarity
Improve docstrings for LLM call events to more accurately describe their purpose and lifecycle
* feat: Add LLMCallFailedEvent emission for tool execution errors
Enhance error handling by emitting a specific event when tool execution fails during LLM calls
