Pin transformers version for DeepSeek-OCR compatibility

Fix ImportError with LlamaFlashAttention2 by pinning to
transformers==4.46.3 and tokenizers==0.20.3 as required
by the model's custom code.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

deepseek-ocr.py

@@ -6,7 +6,8 @@
 #     "pillow",
 #     "torch",
 #     "torchvision",
-#     "transformers",
+#     "transformers==4.46.3",
+#     "tokenizers==0.20.3",
 #     "tqdm",
 #     "addict",
 #     "matplotlib",