Fixed installation error: 'Failed to install context: react-patterns'
Problem:
- Two identical react-patterns.md files existed in different locations
- Registry had duplicate entries with same ID but different paths
- Installation failed due to conflicting entries
Solution:
- Removed duplicate file from development/frontend/react/
- Kept file in ui/web/ (correct location alongside other UI patterns)
- Removed duplicate registry entry
- Now only one react-patterns entry exists
Result:
- ✅ react-patterns installs correctly
- ✅ Registry validation passes
- ✅ No duplicate IDs in registry