Stabilize XTTS sentence endings

platform/docker/tts-gateway/tts_gateway.py

@@ -419,10 +419,23 @@ def _speaker_conditioning() -> dict:
         return SPEAKER_CONDITIONING
 
 
+def _stabilize_xtts_ending(text: str) -> str:
+    """Give XTTS a reliable stop cue without changing the visible answer.
+
+    XTTS v2 can continue with invented syllables after a terminal full stop,
+    especially in German. A terminal semicolon is tokenized as a stronger,
+    more reliable boundary while retaining neutral sentence intonation.
+    """
+    spoken = text.rstrip()
+    if spoken.endswith((".", "!", "?", ";", ":")):
+        spoken = spoken[:-1].rstrip()
+    return f"{spoken};"
+
+
 def _xtts_pcm(text: str, language: str, conditioning: dict) -> bytes:
     payload = {
         **conditioning,
-        "text": text,
+        "text": _stabilize_xtts_ending(text),
         "language": language,
         "add_wav_header": True,
         "stream_chunk_size": "20",