style(agent_utils.py): format imports and code for better readability
refactor(agent_utils.py): standardize model name and cost calculation logic for clarity and maintainability
chore(anthropic_callback_handler.py): create a new file for the AnthropicCallbackHandler implementation and related functions
* feat: add research and planner provider/model options to enhance configurability for research and planning tasks
refactor: create get_effective_model_config function to streamline provider/model resolution logic
test: add unit tests for effective model configuration and environment validation for research and planner providers
* refactor(agent_utils.py): remove get_effective_model_config function to simplify code and improve readability
style(agent_utils.py): format debug log statements for better readability
fix(agent_utils.py): update run_agent functions to directly use config without effective model config
feat(agent_utils.py): enhance logging for command execution in programmer.py
test(tests): remove tests related to get_effective_model_config function as it has been removed
* chore(tests): remove outdated tests for research and planner agent configurations to clean up the test suite and improve maintainability
* style(tests): apply consistent formatting and spacing in test_provider_integration.py for improved readability and maintainability