Add consolidated DeepSeek-OCR GRPO command blocks

[cheatthegod]

Summary

• add single-block Docker command to pull the image, clone EasyR1, install dependencies, and launch DeepSeek-OCR GRPO training
• add single-block native command sequence for venv setup, installation, and training launch
• add troubleshooting note explaining how to resolve a missing examples/deepseek_ocr_grpo.sh error by running from the cloned repo root

Testing

• not run (documentation only)

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Codex Task