v2.7.1

This is a small maintenance release with new model support, localization improvements, and security updates.

Changes

• Add support for OpenAI GPT-6 Astra, Anthropic Claude Fable 5 / 5.1, and Google Gemini 3.8 Flash.
• Improve language and locale handling, including better Chinese script detection and standardized language tags.
• Improve preferred-language instructions sent to AI models.
• Update remaining repository references after the move to ChatGPTBox-dev/chatGPTBox.
• Update dependencies to address security issues reported by npm audit.
• Add related regression tests and minor maintenance updates.

Contributors: @PeterDaveHello

Full Changelog: v2.7.0...v2.7.1