Document Previews

[mgcm]

This PR adds the option to enable saving whiteboard previews (the first slide content) in a new room state event.

This PR makes some opiniated decisions:

• the first slide's SVG data is gziped and base64 encoded in the room state event
• if the resulting data size is larger than 34Kb, the preview content is removed until it can fit again within this size
• a <DocumentPreview /> component that renders the first slide in added to the DOM but hidden - this serves as the source of the preview

:heavy_check_mark: Checklist

• [X] A changeset describing the change and affected packages (more info).
• [X] Added or updated documentation.
• [ ] Tests for new functionality and regression tests for bug fixes.
• [ ] Screenshots or videos attached (for UI changes).
• [X] All your commits have a Signed-off-by line in the message (more info).

[changeset-bot[bot]]

🦋 Changeset detected

Latest commit: a54ca0aedf756419d58598ada251c1a2b94eb80e

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 2 packages

Name	Type
@nordeck/matrix-neoboard-react-sdk	Minor
@nordeck/matrix-neoboard-widget	Patch

Not sure what this means? Click here to learn what changesets are.

Click here if you're a maintainer who wants to add another changeset to this PR