Voice mode: auto-submit after recording stops

Feature Request

Current behavior: After finishing a voice recording, the user must manually press Enter to submit the transcribed message.

Desired behavior: An option to automatically submit the message when voice recording ends (i.e., when the push-to-talk key is released), removing the need for a separate Enter keypress.

Why: When using voice mode hands-free or while multitasking, the extra Enter step adds friction. An auto-submit option (perhaps configurable, since some users may want to review before sending) would make the voice workflow much smoother.