Add cathy, cynda, and james Piper voices for Home Assistant

Three medium-quality en-US single-speaker Piper TTS voices, each with
its .onnx model and .onnx.json config, plus README install instructions.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

.gitignore

@@ -0,0 +1,15 @@
+# OS / editor cruft
+.DS_Store
+Thumbs.db
+*~
+.idea/
+.vscode/
+
+# Python (if you add training/conversion scripts later)
+__pycache__/
+*.pyc
+.venv/
+venv/
+
+# Audio test output
+*.wav