transformer for emacs org-mode file?

## Summary
Please provide a transformer for emacs org-mode file(*.org), like markdown.

Brief explanation of the feature.

### Basic example

Include a basic example or links here.

### Motivation

Why are we doing this? What use cases does it support? What is the expected outcome?

No files, tests, or entry points are named. Start by locating the existing Markdown transformer and comparing its source-file discovery and output behavior; clarify the supported Org-mode syntax and expected result before implementation, with completion requiring an .org file to transform like a Markdown source.

Written by the indexing model from the issue text.