Fix issue parsing object as JSON string

[bjester]

Summary

Description of the change(s) you made

• The public contentnode API sometimes returns an object {} for options, and other times a JSON string "{}" -- this adds defensive checks against that
• Rendering topics in search failed without resource_count
• Changes page size options to reduce likelihood of failed searches
• Changes default page size to 15 instead of 25
• Enforces page size is one of available options
• Adds hacks if we fail to side-load some nodes
• Only loads published nodes when browsing (not searching) through public channels

Manual verification steps performed

1. I manually edited fetchResourceSearchResults Vuex action to use same search API response as on hotfixes
2. I manually edited the public ContentNodeViewset to proxy requests to hotfixes
3. I observed the JSON issue hidden without Sentry reporting
4. Made other changes and verified things still worked locally

Does this introduce any tech-debt items?

The hacky side-loading logic

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Reviewer guidance

How can a reviewer test these changes?

Are there any risky areas that deserve extra testing?

References

#4137 (comment)

Comments

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Contributor's Checklist

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Reviewer's Checklist

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