feat: add uni-comfyui-sdk - Rust SDK for ComfyUI API

- Complete Rust SDK implementation based on OpenAPI specification
- All 23 endpoints implemented with type-safe interfaces
- Comprehensive error handling and async support
- Full documentation and examples included
- Client renamed to UniComfyUIClient for clear identification

cargos/uni-comfyui-sdk/.gitignore

@@ -0,0 +1,20 @@
+# Rust
+/target/
+Cargo.lock
+
+# IDE
+.vscode/
+.idea/
+*.swp
+*.swo
+
+# OS
+.DS_Store
+Thumbs.db
+
+# Logs
+*.log
+
+# Environment
+.env
+.env.local