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>

web-client/index.html

@@ -0,0 +1,38 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+  <meta charset="UTF-8">
+  <meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0">
+  <title>VoiceCoach</title>
+  <link rel="stylesheet" href="style.css">
+</head>
+<body>
+  <div class="container">
+    <div class="header">
+      <h1>VoiceCoach</h1>
+      <div id="status" class="status disconnected">Disconnected</div>
+    </div>
+
+    <div class="controls">
+      <button id="connectBtn" class="btn btn-primary">Start Session</button>
+      <button id="disconnectBtn" class="btn btn-danger" style="display:none">End Session</button>
+    </div>
+
+    <div id="modeDisplay" class="mode-display">Mode: coaching</div>
+
+    <div id="transcript" class="transcript">
+      <p class="hint">Press "Start Session" to connect your voice.</p>
+    </div>
+
+    <div class="mode-buttons">
+      <button class="mode-btn" onclick="setMode('coaching mode')">Coaching</button>
+      <button class="mode-btn" onclick="setMode('vent mode')">Vent</button>
+      <button class="mode-btn" onclick="setMode('practice mode')">Practice</button>
+      <button class="mode-btn" onclick="setMode('briefing mode')">Briefing</button>
+    </div>
+  </div>
+
+  <script src="https://cdn.jsdelivr.net/npm/livekit-client/dist/livekit-client.umd.min.js"></script>
+  <script src="app.js"></script>
+</body>
+</html>