- Migrate `compress_image.go` to `internal/imageutil` for better encapsulation.
- Reorganize LLM provider implementations into distinct packages (`google`, `openai`, and `anthropic`).
- Replace `go_llm` package name with `llm`.
- Refactor internal APIs for improved clarity, including renaming `anthropic` to `anthropicImpl` and `google` to `googleImpl`.
- Add helper methods and restructure message handling for better separation of concerns.
Introduce `Response()` and `ToolCall()` methods to access the respective fields from the `Context` struct. This enhances encapsulation and provides a standardized way to retrieve these values.
Simplified how responses and tool calls are appended to conversations. Adjusted structure in message formatting to better align with tool call requirements, ensuring consistent data representation.
