Docs: Move legacy docs pages and add admonitions

[adiati98]

Description

This PR moves legacy docs pages to the new docs with details as follow:

• Pages contain the main title and a note admonition that redirect readers to the legacy repository.

Linked issue

N/A

Screenshots or screen recordings

[adiati98]

In the legacy repo, this is a standalone page: https://github.com/mautic/developer-documentation/blob/main/source/includes/_api_rate_limiter.md.

Can this be part of API intro here, or is it part of another page (if so, which one?), or should it be a standalone page as the legacy?

[RCheesley]

The API rate limiter was removed, actually - since 7 I think. But we should have it there for legacy reasons. I think it makes sense having it in the API intro but open to thoughts on that from the devs.

[adiati98]

@escopecz do you have any thoughts about this?

[escopecz]

I'd remove it. One company added the feature and it was removed because there was no version of the library that would support new Symfony and PHP version. The company was notified about it in time and they didn't add a replacement so far. So I hope this feature won't be missed by anyone.

[adiati98]

In the original version, "Channels" section is not available, and "Extending broadcast" sub-section in this page is a standalone page: https://github.com/mautic/developer-documentation/blob/main/source/includes/_plugin_extending_broadcasts.md.

Is this correct that "Channels" and "Extending broadcast" are in the same page?

[RCheesley]

Yes, I think extending broadcasts should sit under channels, because it relates to sending emails, SMS etc which are all channels.

[adiati98]

@RCheesley @escopecz

I've moved all pages from the legacy repo. I have a couple of questions in the comments in the files, and I'd like you to:

• Review if the pages structure are make sense and in flow. If not, please let me know how we want to structure them.
• Let me know which pages/toctrees that we want to remove from docs.

TIA! ✨

[RCheesley]

Couple of small ones, thanks so much for doing this grunt work @adiati98 !

[adiati98]

Thanks for the approval, @RCheesley! Once it's merged, I'm getting ready for the merge conflicts from the outstanding PRs. 😁 💪🏼

[RCheesley]

GTG once we get a 👀 from a dev team member :)

[escopecz]

I'm thinking whether we shouldn't drop the outdated docs, but it may help someone. Let's try this