Allow different Provider for Transcript and AI Mode to combine speed in Transcription and quality in AI

My issue is that I would love the speed of Groq and the AI mode quality of Sonnet.
As Groq does not support Sonnet, I need to decide between the two of those.

So I use Ppenrouter for transcribtion as well as AI Mode.
Would be great if I could select Groq for transcription and OpenRouter for AI Mode.