util/tools/expression library

1. agentic package
2. documentation
3. util/tools/expression.dart

agentic package

1. Libraries
2. agentic
3. chat/agent/agent
4. chat/agent/chat_provider
5. chat/agent/transformer
6. chat/connector/chat_request
7. chat/connector/connected_model
8. chat/connector/connector
9. chat/connector/connector_anthropic
10. chat/connector/connector_gemini
11. chat/connector/connector_inception
12. chat/connector/connector_naga
13. chat/connector/connector_ollama
14. chat/connector/connector_openai
15. chat/connector/connector_openrouter
16. chat/connector/connector_xai
17. chat/connector/model
18. chat/connector/result
19. chat/content/content
20. chat/content/content_audio
21. chat/content/content_group
22. chat/content/content_image
23. chat/content/text_content
24. chat/message/message
25. chat/message/message_agent
26. chat/message/message_system
27. chat/message/message_tool
28. chat/message/message_user
29. chat/tool/tool
30. chat/tool/tool_call
31. chat/tool/tool_schema
32. gen/artifacts.gen
33. ingest/chunker
34. ingest/distiller
35. ingest/test
36. test
37. util/chat_models
38. util/codec
39. util/cost
40. util/naga_models
41. util/open_router_models
42. util/tools/expression