Add starter structure for demucs/tts demos and .gitignore

Co-Authored-By: Claude Sonnet 5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01SN15Vxn4svKuhYxFsVtMJf

.gitignore

@@ -0,0 +1,27 @@
+.env
+
+# Python
+__pycache__/
+*.pyc
+.venv/
+venv/
+
+# Model weights / large artifacts
+*.pt
+*.ckpt
+*.bin
+*.safetensors
+models/
+weights/
+
+# Audio I/O scratch
+*.wav
+*.mp3
+*.flac
+output/
+outputs/
+
+# OS/editor
+.DS_Store
+.idea/
+.vscode/