feat: initial commit — VoiceCoach real-time voice coaching pipeline

Services: Pipecat agent (LiveKit + Claude + Whisper STT + Piper TTS),
SpeechBrain analysis service, Piper TTS service, web client (nginx).
Includes LiveKit server config and docker-compose orchestration.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

pipecat-agent/requirements.txt

@@ -0,0 +1,10 @@
+pipecat-ai[livekit,silero,openai]==0.0.48
+anthropic==0.34.0
+faster-whisper==1.0.3
+requests==2.32.3
+httpx==0.27.0
+python-dotenv==1.0.1
+structlog==24.4.0
+numpy==1.26.4
+soundfile==0.12.1
+livekit-api==0.7.1