Add hardware: zero-gpu to Space metadata

Without this the Space runs on CPU-only hardware and model.cuda()
fails with 'Found no NVIDIA driver'. The @spaces.GPU decorator only
allocates a ZeroGPU slot when the Space is configured for it.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

README.md

@@ -10,6 +10,7 @@ pinned: true
 short_description: DeepSeek-OCR-2 with MathJax math rendering
 license: mit
 python_version: "3.12"
+hardware: zero-gpu
 ---
 
 # DeepSeek-OCR-2 — Math Rendering Edition