[Dashboard] Provide a dedicated video embed panel

[ryankeairns]

Relates to #57241

As part of the dashboard redesign, allow users to embed video as a panel in a dashboard.
It would be good to have an explicit add video panel where users can add a video embed URL as part of the dashboard toolbar.

Assumption

We only support embedded video to avoid the complexities of storage.

Tasks

Dependencies

• File storage service

Plugin & Services

See this same section for the image panel issue
Presuming it would be built first, there may be prior art to follow once we're ready to add video.

Design & UI

• Should allow entering a link to a hosted video

Dashboard Integration

• Add as quick button on toolbar and editor menu option in Dashboard (and Canvas?)

[elasticmachine]

Pinging @elastic/kibana-presentation (Team:Presentation)

[ThomThomson]

@Dosant, @vadimkibana, I wonder if this could be accomplished with an extension to the Image Embeddable? I assume that we wouldn't want to allow the user to upload a video straight into ES, but providing an external URL could work.

Keeping this open for the time being with an impact:low, and a multi-week LOE.

[ThomThomson]

Closing this for the time being as we aren't able to prioritize large dashboard features with limited use-cases at the moment.