fix(realtime): Set the alias for opus so the development backend can be selected (mudler#9083)

Signed-off-by: Richard Palethorpe <io@richiejp.com>

Author: richiejp

backend/index.yaml

@@ -726,6 +726,7 @@
     - TTS
 - &opus
   name: "opus"
+  alias: "opus"
   uri: "quay.io/go-skynet/local-ai-backends:latest-cpu-opus"
   urls:
     - https://opus-codec.org/