[FEATURE] Voice mode: add French language support

Feature Request

Description

Voice mode currently only supports English speech-to-text. It would be great to add support for French (and potentially other languages).

Use Case

As a French-speaking developer, I use Claude Code daily and would love to use voice mode in my native language. Currently, speaking French to the voice input results in poor recognition or no detection at all.

This is related to the broader i18n request in #7233, but specifically targets the voice/speech-to-text pipeline.

Suggested Behavior

• Allow users to configure the voice input language (e.g., via settings.json or a /voice language command)
• Support at least major languages: French, German, Spanish, Japanese, etc.
• Ideally, auto-detect the spoken language

Environment

• Claude Code v2.1.71
• Windows 11 / macOS