Adding Variable Component Types

**Is your feature request related to a problem? Please describe.**

There are front-matter configurations that can accept both a piece of text and a boolean value of false, such as [this one](https://redefine-docs.ohevan.com/en/article_customize/excerpt).

**Describe the solution you'd like**

Provide a list in the UI where you can choose whether his type is bool or image and change its value after choosing the type.

**Describe alternatives you've considered**

I tried Variable Type Widgets and he doesn't seem to be like that.

**Additional context**