Update documentation to 128K context

reorganize: consolidate root level to 20 folders

fix: update benchmark paths in stack-2.9-cli.py and remove deprecated cli/ module

Add tools, fix web search, update model

fix: support input_path in train_lora for JSONL files

fix: add train_dir and eval_dir to config for Kaggle

feat: combine RTMP tools with main training data

fix: use absolute paths and fix bitsandbytes version

feat: Add free deployment support for Stack 2.9

refactor: Squeeze folders further - cleaner structure