When LLM.call() is invoked with both tools and available_functions,
it now runs a tool loop — calling the model, executing requested tools,
and feeding results back — until the model responds with text or
max_iterations is reached.
Changes:
- New llm_result.py with LLMResult and ToolCallRecord models
- LLM.call() returns LLMResult (structured) when tools are provided,
str when not (fully backwards compatible)
- Tool loop with max_iterations parameter (default 10)
- Cost estimation based on model name and token counts
- Comprehensive test suite (17 tests, all mocked)
- Exports LLMResult and ToolCallRecord from crewai.__init__
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