Initial commit: Voice Assistant Gateway mit Konfig-/Routing-Fundament

- FastAPI-Gateway mit REST-Endpunkten (chat/speak/transcribe/devices/sessions/config)
- Geschichtete Konfiguration mit Profilen (local-dev/hybrid/cloud) via TOML + ENV
- Registry-Pattern + einheitliche Route-Aufloesung (Default->Profil->ENV->Session->Request)
- Device Router (strikt, Singleton) und Output-Lifecycle im Orchestrator
- OpenRouter-Adapter (STT multipart/LLM/TTS) + lokale Provider-Stubs
- Regelbasierte Pipeline (Cleaner/Spoken-Adapter/TTS-Normalizer)
- 22 automatisierte Tests; Doku: README, BEDIENUNGSANLEITUNG, Architektur
- Secrets ausschliesslich ueber Umgebung; .env und lokale config gitignored

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

chat_client.py

@@ -0,0 +1,76 @@
+import io
+import wave
+import requests
+import soundfile as sf
+import numpy as np
+import subprocess
+import sys
+
+GATEWAY_URL = "http://localhost:8003"
+CHAT_ENDPOINT = f"{GATEWAY_URL}/api/chat"
+
+# feste Annahmen für Gemini 3.1 Flash TTS über OpenRouter
+SAMPLE_RATE = 24000
+CHANNELS = 1
+SAMPLE_WIDTH = 2  # 16-bit PCM
+
+
+def pcm_to_wav(pcm_bytes: bytes, wav_path: str) -> None:
+    """Rohes s16le-PCM in eine WAV-Datei schreiben."""
+    with wave.open(wav_path, "wb") as wf:
+        wf.setnchannels(CHANNELS)
+        wf.setsampwidth(SAMPLE_WIDTH)
+        wf.setframerate(SAMPLE_RATE)
+        wf.writeframes(pcm_bytes)
+
+
+def play_wav(wav_path: str) -> None:
+    """WAV-Datei abspielen (ffplay oder aplay/mpv, je nach System)."""
+    for cmd in (
+        ["ffplay", "-nodisp", "-autoexit", wav_path],
+        ["aplay", wav_path],
+        ["mpv", wav_path],
+    ):
+        try:
+            subprocess.run(cmd, check=True)
+            return
+        except (FileNotFoundError, subprocess.CalledProcessError):
+            continue
+    print(f"Konnte keine geeignete Player-CLI finden für {wav_path}", file=sys.stderr)
+
+
+def chat_and_play(text: str, language: str = "de") -> None:
+    payload = {"text": text, "language": language}
+
+    resp = requests.post(
+        CHAT_ENDPOINT,
+        json=payload,
+        stream=True,
+    )
+
+    if not resp.ok:
+        print("HTTP", resp.status_code)
+        print(resp.text)
+        return
+
+    pcm_bytes = b"".join(resp.iter_content(chunk_size=8192))
+
+    # Hinweis: Den Text-Trace (Transkript/Antwort) liefert /api/chat nur im JSON,
+    # wenn man ?debug=true anhängt - nicht als Header im Audio-Stream.
+    print("Audio-Format:", resp.headers.get("X-Audio-Format"))
+    print("Sample-Rate:", resp.headers.get("X-Audio-Sample-Rate"))
+
+    wav_path = "chat_reply.wav"
+    pcm_to_wav(pcm_bytes, wav_path)
+    print(f"WAV gespeichert unter {wav_path}")
+    play_wav(wav_path)
+
+
+if __name__ == "__main__":
+    if len(sys.argv) > 1:
+        user_text = " ".join(sys.argv[1:])
+    else:
+        user_text = "Wie wird das Wetter morgen in Bünde?"
+
+    chat_and_play(user_text, language="de")
+