Fixes loading spinner issue

[akolson]

Summary

Description of the change(s) you made

This pr fixes the continuous loading spinner when previewing a searched channel resource.

Manual verification steps performed

• Select a channel
• Click "Add" button, then select "Import from other channels"
• Search for channel resources using a desired keyword
• Click on the result card(s) that come(s) up
• Preview modal opens but spinner keeps on loading

Reviewer guidance

How can a reviewer test these changes?

• Select a channel
• Click "Add" button, then select "import from other channels"
• Search for channel resources using a desired keyword
• Click on the result card(s) that come(s) up
• Preview modal should display information about the selection

References

Fixes #3956

Comments

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Contributor's Checklist

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Reviewer's Checklist

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[bjester]

Nice work! It does indeed show something other than the loading spinner

Although, since the search API doesn't return all pertinent info about the node, the details are inaccurate. I'll write up a followup issue for that, since that is more likely a P1 that we can fix later.

[bjester]

There was one unrelated issue that I saw when trying to complete the import of a node I previewed and added from the side panel. I think it's best to merge this and verify it in conjunction with Richard's change event updates on the unstable server.

TypeError: Cannot read properties of undefined (reading 'original_source_node_id')
    at TreeResource.tableCopy