[ISSUE #15435] Improve next console AI resource version diff

[saynoword]

Please do not create a Pull Request without creating an issue first.

Fixes #15435

What is the purpose of the change

Improve the next console AI resource detail experience by adding version diff support for Skill and Prompt resources, and by refining resource file editing actions so version review and draft editing are easier to use from the UI.

Brief changelog

• Add Skill version diff support for added, removed, and modified files.
• Add Prompt version diff support for template content.
• Refine Skill resource editing with a file header action area and clearer text/non-preview file handling.
• Align AgentSpec resource editing actions with the Skill resource editing experience.
• Normalize Skill markdown preview for prompt-style heading separators.
• Sync generated next console static assets.

Verifying this change

• node -e "JSON.parse(require('fs').readFileSync('console-ui-next/src/locales/zh-CN.json','utf8')); JSON.parse(require('fs').readFileSync('console-ui-next/src/locales/en-US.json','utf8')); console.log('locales ok')"
• git diff --check
• Not run: frontend build in this iteration; static assets were committed from the existing generated output.

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[github-actions]

Thanks for your this PR. 🙏
Please check again for your PR changes whether contains any usage/api/configuration change such as Add new API , Add new configuration, Change default value of configuration.
If so, please add or update documents(markdown type) in docs/next/ for repository nacos-group/nacos-group.github.io

---

感谢您提交的PR。 🙏
请再次查看您的PR内容，确认是否包含任何使用方式/API/配置参数的变更，如：新增API、新增配置参数、修改默认配置等操作。
如果是，请确保在提交之前，在仓库nacos-group/nacos-group.github.io中的docs/next/目录下添加或更新文档（markdown格式）。

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.

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