feat: add remark plugin to rewrite localized links in Markdown content

[bjohansebas]

A remark plugin to make it easier to reference links that are versioned and obviously have i18n. This will also greatly help prevent links from breaking when content is translated in Crowdin.

TODOs:

• Update the content to remove the 5x or 4x prefixes and remove {page.lang} (after this PR, we can start better localizing our content).
• Add unit tests for this.
• Add references in the contributing guide explaining this and how it works.

Also, it would be great to have #2192 merged first to ensure that links are always working properly.

This was generated with GitHub Copilot and reviewed by me.

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[bjohansebas]

This is completely temporary, just to test that it’s working for i18n.

[ShubhamOulkar]

This is a useful plugin. I’ll start looking into it once we reach a solid stage in the redesign. I just don’t want to overload myself right now.