Support Japanese language output for /context command

Preflight Checklist

• [x] I have searched existing requests and this feature hasn't been requested yet
• [x] This is a single feature request (not multiple features)

Problem Statement

Currently, the /context command output is only available in English.
Japanese-speaking developers find it difficult to read context usage information displayed in English.
Supporting native language output would significantly improve usability for non-English users.

Proposed Solution

Enable /context command output to display in Japanese.
Alternatively, allow users to set language preferences to Japanese in their configuration.

Alternative Solutions

_No response_

Priority

High - Significant impact on productivity

Feature Category

CLI commands and flags

Use Case Example

When working on a Japanese project, running /context displays context usage statistics in Japanese.
This allows developers to monitor token consumption and context efficiency in their native language.

Additional Context

_No response_