feat: escape single open brackets after a close bracket

[eaglethrost]

	Fix RM-XYZ

Context

For a text with an opening bracket right after a complete bracket, the remark library will drop the second opening bracket because it thinks the second part is part of the link reference, will start parsing it as such, but when no closing bracket was found, it only retains the text.

[bar][bar -> [bar]bar

This may look unexpected for users, so this PR provides a workaround to retain the second opening bracket by visiting the tree and regex escaping it, so that it can be retained.

🧰 Changes

Created an additional plugin to the processor to revisit the created AST of a markdown, visits linkRefernce nodes, and compares span recorded in the node positions with the expected [label] length to find dropped ['s & replace it with text node with the bracket reattached

I used this approach instead of just escaping the brackets because it was hard for me to distinguish if the text is inaccurate code block, jsx, etc where we don't want to touch it.

Let me know if there's another approach or if this is too complicated for this case, I feel like the amount of cases of this appearing would be low.

🧬 QA & Testing

• Broken on production.
• Working in this PR app.

[kellyjosephprice]

I don't believe this is going to work as expected. The @readme/markdown@6 is only used to parse to an AST during the migration. The 'compilation' to a string is all done by '@readme/markdown@>11'. My recommendation would be to move all of this into @readme/markdown@11.

We pass in custom migration specific transformers here: https://github.com/readmeio/markdown/blob/next/lib/mdastV6.ts#L13

We don't really have a concept of migration only compilers, but that would be easy to add. Perhaps a new option for passing in compilers here: https://github.com/readmeio/markdown/blob/next/lib/migrate.ts#L14-L17