Issue fields [GA]

### Value Prop

We want to make it easier to share and sync item information across projects. This will make it easier to keep items and their metadata up to date and remove the need for manual updates and edits.

### Expected Outcome

By helping keep information up-to-date across multiple projects, teams can rely on a single source of truth where critical details remain consistent, easy to find, and free from manual effort.

该 issue 中没有指定文件、测试或入口点。首先明确哪些 issue 字段必须在项目之间同步、冲突和更新应如何处理，以及支持哪些项目类型；当项目项目信息无需手动编辑即可保持一致时，工作就完成了。

由索引模型根据 Issue 内容生成。