docs(realtime): explain transcript language tags

Assisted-by: Codex:gpt-6
Signed-off-by: nexxtmobile.de <git@nexxtmobile.de>

docs/content/features/openai-realtime.md

@@ -33,6 +33,11 @@ Make sure all referenced models (`silero-vad-ggml`, `whisper-large-turbo`, `qwen
 
 A pipeline stage can name a [failover chain]({{%relref "features/model-failover" %}}); the stage then switches targets without closing the session.
 
+Transcription backends can include end-of-utterance language tags, such as `<en-US>` or `<de-DE>`.
+LocalAI removes these tags from the user transcript sent to the LLM.
+The transcription events sent to the client retain the original tags.
+This prevents a tag from overriding the intended conversation language in the LLM context.
+
 ### Install the Qwen streaming assistant preset
 
 The gallery entry `qwen3-streaming-assistant` configures an English voice