replace local notebook path with live Colab URL

README.md

@@ -29,7 +29,7 @@ Team **BalleBalle**: Amrinder Singh, Shubham Kapoor.
 - Trained model: https://huggingface.co/aamrinder/subtext-arena-grpo
 - Blog post (under 2 min read): [blog.md](blog.md)
 - Side-by-side demo (5 hero clips, baseline vs trained): [docs/side_by_side.html](docs/side_by_side.html)
-- Colab notebook (re-run the training): [notebooks/train_grpo_colab.ipynb](notebooks/train_grpo_colab.ipynb)
+- Colab notebook (re-run the training): https://colab.research.google.com/drive/1PL_nc6oiLahPiReKG-x8CWCBarCUR3qc?usp=sharing
 
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@@ -136,7 +136,7 @@ hf jobs uv run --flavor l4x1 -s HF_TOKEN \
        --push-to-hub aamrinder/subtext-arena-grpo
 ```
 
-A Colab-friendly version of the same script is at [notebooks/train_grpo_colab.ipynb](notebooks/train_grpo_colab.ipynb).
+A Colab-friendly version of the same script is at https://colab.research.google.com/drive/1PL_nc6oiLahPiReKG-x8CWCBarCUR3qc?usp=sharing.
 
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