feat: remove json index on search-hidden pages

[Singularity0909]

What does this PR change? What problem does it solve?

To remove JSON index on the page set search-hidden param as true.

Was the change discussed in an issue or in the Discussions before?

No.

PR Checklist

• [ ] This change adds/updates translations and I have used the template present here.
• [x] I have enabled maintainer edits for this PR.
• [x] I have verified that the code works as described/as intended.
• [ ] This change adds a Social Icon which has a permissive license to use it.
• [x] This change does not include any CDN resources/links.
• [x] This change does not include any unrelated scripts such as bash and python scripts.
• [ ] This change updates the overridden internal templates from HUGO's repository.

I'm not sure about the last check item.

[sonarcloud[bot]]

Quality Gate passed

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[Singularity0909]

How does this affect Search? json schema has no effect on search.

For context searchHidden is to hide pages from site's search index and not for any search engine's

@adityatelange Thanks for reviewing. In my view, currently the JSON index only works for blog searching, and it will be useless when the search function is turned off.

Sometimes I need to encrypt partial content of my blog pages.

https://github.com/Li4n0/hugo_encryptor

Through this tool, some parts of an article will be encrypted with AES and encoded into base64. However, JSON of the entire original content in the header of the webpage cannot be encrypted, which may be spied on.