ci(lang): sync only new fields

[KirCute]

Description / 描述

解决drivers.json和settings.json两个翻译文件总是被 bot 覆盖的问题。

Motivation and Context / 背景

How Has This Been Tested? / 测试

Checklist / 检查清单

• I have read the CONTRIBUTING document.
  我已阅读 CONTRIBUTING 文档。
• I have formatted my code with go fmt or prettier.
  我已使用 go fmt 或 prettier 格式化提交的代码。
• I have added appropriate labels to this PR (or mentioned needed labels in the description if lacking permissions).
  我已为此 PR 添加了适当的标签（如无权限或需要的标签不存在，请在描述中说明，管理员将后续处理）。
• I have requested review from relevant code authors using the "Request review" feature when applicable.
  我已在适当情况下使用"Request review"功能请求相关代码作者进行审查。
• I have updated the repository accordingly (If it’s needed).
  我已相应更新了相关仓库（若适用）。
  • OpenList-Frontend #XXXX
  • OpenList-Docs #XXXX

[Copilot]

Pull request overview

This PR addresses an issue where translation files (drivers.json and settings.json) were being completely overwritten by a bot. The solution implements a merge strategy that only syncs new fields from the generated data into existing translation files, preserving manually translated content.

Key Changes:

• Replaced reflect.DeepEqual comparison with a custom mergeJson function that merges only new fields
• Modified the write logic to save the merged oldData (with new fields added) instead of completely replacing with newData
• Removed the unused reflect package import

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