fix: Remove non-existent @spaces.CPU decorator

- Remove @spaces.CPU decorator (doesn't exist in spaces module)
- Keep only @spaces.GPU which is the required decorator
- Fixes AttributeError: module 'spaces' has no attribute 'CPU'

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

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

app.py

@@ -96,10 +96,9 @@ def _dummy_gpu_function():
     """Dummy function to satisfy ZeroGPU startup detection"""
     return "GPU available"
 
-# Dummy CPU function to satisfy Spaces CPU requirements
-@spaces.CPU
+# Regular CPU function (no decorator needed)
 def _dummy_cpu_function():
-    """Dummy function to satisfy Spaces CPU detection"""
+    """Regular CPU function for system info"""
     return "CPU available"
 
 # Initialize functions at module level for Spaces detection