Update README.md

Add project directory structure.

README.md

@@ -94,6 +94,37 @@ This repository is in active development. We're building:
 - Evaluation metrics
 - Demo applications
 
+Project directory structure:
+opentunes-ai/
+├── README.md           # Contains metadata + documentation
+├── models/
+│   ├── melody-gen/    # First model
+│   │   ├── config/
+│   │   │   ├── model_config.json
+│   │   │   └── training_config.json
+│   │   ├── weights/
+│   │   │   └── v0.1.0/
+│   │   └── examples/
+│   │       ├── input_prompts.json
+│   │       └── generated_samples/
+│   └── lyrics-gen/    # Second model
+│       ├── config/
+│       ├── weights/
+│       └── examples/
+├── notebooks/
+│   ├── melody_development.ipynb
+│   └── lyrics_development.ipynb
+├── datasets/          
+│   ├── melodies/
+│   └── lyrics/
+└── spaces/           # Gradio demos
+    ├── melody-demo/
+    └── lyrics-demo/
+
+Add .gitattributes for git-lfs
+.gitattributes        # Specify files for git-lfs tracking
+
+
 ## 🤝 Contributing
 We welcome contributions from the community! Whether you're interested in:
 - Model development