Indicate library-sourced content (Authoring MFE - Unit Page)

[bradenmacdonald]

When components are linked to a v2 content library, display that with an icon in the component header. This screenshot shows the working implementation on the legacy unit page; implement the same thing on the new MFE unit page.

Notes:

• The "Update available" button/workflow is a separate story
• The newsstand icon needs to be added to Paragon and is the same icon specified for Improve Add from Library buttons (Authoring MFE - Unit Page) #1462
• If the upstream link is broken/invalid, display the Paragon LinkOff icon and the hovertext/title should say "Sourced from a library - but the upstream link is broken/invalid.". See legacy UI implementation.
• The icon has hovertext/tooltip but is not clickable. Clicking on it should not have any effect.
• See this PR that implemented the legacy version

[bradenmacdonald]

@jmakowski1123 FYI

[jmakowski1123]

cc @GlugovGrGlib for visibility. These are small additions being made to the new unit page MFE.

[bradenmacdonald]

@rpenido With the work being done on the iframe, it seems the only thing left to do here is fix the tooltip so it doesn't get cut off when the legacy view is embedded in the iframe.

[ChrisChV]

@bradenmacdonald @jmakowski1123 Is it okay to move this to Done?