docs: extends validation error and validation error items explanation

[fzn0x]

Pull Request Checklist

Please make sure to review and check all of these items:

• Have you added new tests to prevent regressions?
• Does npm run test or npm run test-DIALECT pass with this change (including linting)?
• Is a documentation update included (if this change modifies existing APIs, or introduces new ones)?
• Did you update the typescript typings accordingly (if applicable)?
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Description Of Change

Closes #13812

Todos

• Fix unnecessary block tags in ValidationError class multiline comment
• Expand validation error item parameters

[fzn0x]

Change it to draft since it's depends on Docusaurus PR. #13769

[WikiRik]

@fzn0x do you want to reopen this?

[ephys]

All changes are already included thanks to Typedoc properly extracting the information from the jsdoc (which esdoc failed to do), and I think #14002

• ValidationErrorItem
• ValidationError
• ValidationError#get

@fzn0x if you confirm, can you delete the unmerged branch?

[fzn0x]

Removed, thanks @sdepold @WikiRik @ephys :)