Add toggle to skip inserting "No speech detected" message

[lucyfarnik]

Summary

• Adds an "Insert No Speech Message" toggle under Output Options in Transcription settings
• When disabled, prevents "No speech detected in the audio" from being pasted into the active window
• Useful when the mic picks up silence or background noise

Test plan

• Enable the toggle (default) and verify "No speech detected" is pasted when no speech is recognized
• Disable the toggle and verify nothing is pasted when no speech is detected
• Verify normal transcriptions still work with the toggle in either state

[Starmel]

I don’t want to see another simple toggle. It would be better to remove the text “No speech detected in the audio” from being pasted at all.

Thank you.