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The main change in this PR fixes the snapshot functionality in the Publish pane-related components. Because the code cell outputs are now rendered in their own iframes for security reasons, a single snapshot of the notebook is no longer possible: each cell output takes its own snapshot and the snapshots are collated on the main notebook snapshot.
- Move the snapshot functionality to notebook components: this removes the reference of the notebook DOM node that we must pass to the Publish pane via explorer.
- Add slice in the state and actions in notebook redux for notebook snapshot requests and result
- Add post robot message to take snapshots and receive results
- Add logic in `NotebookRenderer` to wait for all output snapshots done before taking the main one collating.
- Use `zustand` to share snapshot between Redux world and React world. This solves the issue of keeping the `PanelContainer` component generic, while being able to update its children (`PublishPanel` component) with the new snapshot.
Additional changes:
- Add `local()` in `@font-face` to check if font is already installed before downloading the font (must be done for Safari, but not Edge/Chrome)
- Add "Export output to image" menu item in notebook cell, since each cell output can take its own snapshot (which can be downloaded)
* Added support for taking screenshot
- Screenshot is taken using html2canvas package
- Converted to base 64 and uploaded to metadata
- For Using first display output
- Notebok object is passed instead of string, to publish pane
- The first cell with output present is parsed out
- The dom is also parsed to get corresponding div element to take screenshot of the first output
* fixed bug
* Addressed PR comments
- FIxed bug that didn't capture screenshot when mutiple notebook tabs are opened
* removed unnecessary dependencies
* fixed compile issues
* more edits
