adds documents to linkit profile

[markconroy]

Closes #253

What does this change?

• Adds documents as an allowed type in the LinkIt matchers.
• Sets the URL to be "canonical" (/media/123 - I think). Would we prefer this to be "Direct link to the media file"?

How to test

Try to link to a document in a wysiwyg, you should see "Document: [media - name]" for available documents in your linkit suggestions.

Have we considered potential risks?

I'm not fully sure what happens when a document is changed/gets a new file.

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Thanks to Big Blue Door for sponsoring my time to work on this.

[finnlewis]

Sounds like we need a bit of testing.
Hoping @ekes might be able to explain the complexity.

Also: some councils are using less ckeditor embedded buttons and are using paragraphs more.

[finnlewis]

What is the expected behaviour of a LinkIt link to a document?

Is it:

a) to the canonical url of the media item (/media/123)
b) to the file that is the target of the media item? (/sites/default/files/my-file.pdf)
c) to a download link (/media/123/download)

[finnlewis]

I think this is with @willguv to check with content people.

[stephen-cox]

Discussing this again at Merge Tuesday - need to understand the tech complexities - will create a Slack chat on this.

[finnlewis]

@willguv have you had a chance to chat about this one with content people yet? Thanks dude!

[willguv]

Hi @finnlewis not yet sorry - thanks for the nudge

Can we describe in content designer language what this PR describes? Or can we spend a bit of our session next Monday looking at it/ writing something?

[finnlewis]

Discussing this with @willguv , this is part of a bigger review about how we want to guide people on best practice for displaying documents. Converting to draft for now.