Split train and tool simulator modules; mastery curriculum and grader workflow nudge.

feat: default GRPO/eval to Qwen/Qwen3-1.7B + LoRA; disable Qwen3 thinking in chat template

Update notebooks and proof artifact tooling

Harden notebook vLLM compatibility checks

Trim notebook install dependencies

Fix OpenEnv and HF training flows

Docs: align with Hugging Face Hub + TRL official guides

Fix Colab TRL+vLLM: pin vllm<0.19, add tomli deps, guard train

Colab/Kaggle: auto GPU profile for bf16+vLLM on A100/L4

Diagnostic: track parse_ok_ratio per episode, dump health every 5 episodes

Fix flat-reward training: stronger SYSTEM_PROMPT with few-shot, longer completions, MAX_TURNS=16, schema sanity probe

Rename files to DriftShield: notebooks, server module, kernel folder

DriftShield Phase C: README pivot + driftshield_easy as default curriculum

Explain GitHub import vs Kaggle Internet; friendlier gaierror in network check

Notebook UX: split pip vs imports; warn against Ctrl+C during DNS retries

Docs: clarify pip DNS failures; add pre-install network check cells

Add Kaggle training notebook, kernel metadata, and push script