Feature request: Allow session title language to be configured (e.g., via CLAUDE.md)

Summary

Session titles in Claude Code Desktop are always generated in English, even when the user exclusively communicates in Japanese (or another non-English language). There is currently no way to configure the language used for session title generation.

What I tried

• Adding a rule to project-level CLAUDE.md: 新規セッションのタイトルは必ず日本語で命名する（英語禁止）
• Adding the same rule to global ~/.claude/CLAUDE.md
• Neither had any effect — titles remained in English

Expected behavior

Session titles should respect either:

1. A configurable setting (e.g., in settings.json or CLAUDE.md) for the preferred title language
2. The language of the user's input messages (auto-detect)
3. The system locale

Why this matters

For non-English-speaking users, English session titles make it harder to quickly scan and find past sessions. Japanese (or localized) titles would significantly improve the session management experience.

Environment

• Claude Code Desktop on Windows 11
• Primary language: Japanese