I would like to contribute a MarkdownHeaderTextSplitter for Javascript, currently only available in python

[mstein11]

Checked

• I searched existing ideas and did not find a similar one
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Feature request

The python version of langchain has MarkdownHeaderTextSplitter, which adds information regarding the headline Hierachy as metadata to each chunk.

The js version of langchain is lacking such a functionality.

I already implemented a js version of this functionality here: https://github.com/mstein11/Ellie/tree/main/lib/vectorstore/HierachicalMarkdownTextSplitter

I would be happy to open a PR, if the maintainers agree, that such a functionality adds value to js langchain.

I would need some guidance for navigating the contribution process in this repository, however.

Motivation

I already implemented said functionality and would like to share it as a PR, what is the preferred way to open the PR?

Proposal (If applicable)

No response