feat: Integrate file tools and LLM tool calling support
- Implemented structured ToolResponse format in src/tools/tool-response.ts for standardized outputs with fields like success, errors, result, and version.
- Refactored file tools in src/tools/file/ to return ToolResponse POJOs from execute methods: create_file, delete_file, edit_file, find_file, list_dir, rename_file, tree_dir, and read_file.
- Updated ReAct loop in src/repl-orchestrator.ts to serialize ToolResponse to JSON before appending to history and added repetition detection with a max loop limit of 2.
- Revised main system prompt in src/prompts/main_agent.md to describe ToolResponse interpretation and updated usage examples accordingly.