fix: update setup script to install PaddlePaddle GPU version from official source

Changes to setup_dev_env.sh:
- Add support for CUDA 13.x (install CUDA 12.x compatible version)
- Use official PaddlePaddle source for GPU versions
- Install paddlepaddle-gpu==3.0.0b2 from official index
- CUDA 13.x: use cu123 package (backward compatible)
- CUDA 12.x: use cu123 package
- CUDA 11.7+: use cu118 package
- CUDA 11.2-11.6: use cu117 package

Changes to requirements.txt:
- Comment out paddlepaddle dependency
- Let setup script handle GPU/CPU version installation

This fixes the issue where pip installed CPU-only paddlepaddle 3.2.1
instead of GPU version, causing GPU acceleration to be unavailable.

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

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

requirements.txt

@@ -10,7 +10,7 @@ email-validator>=2.0.0  # For pydantic EmailStr validation
 
 # ===== OCR Engine =====
 paddleocr>=3.0.0
-paddlepaddle>=3.0.0
+# paddlepaddle>=3.0.0  # Installed separately in setup script (GPU/CPU version)
 paddlex[ocr]>=3.0.0  # Required for PP-StructureV3 layout analysis
 
 # ===== Image Processing =====