Clarify help texts related to JSON and CBOR

[carbolymer]

Changelog

- description: |
    Clarify help texts related to JSON and CBOR
# uncomment types applicable to the change:
  type:
  # - feature        # introduces a new feature
  # - breaking       # the API has changed in a breaking way
  # - compatible     # the API has changed but is non-breaking
  # - optimisation   # measurable performance improvements
   - refactoring    # QoL changes
  # - bugfix         # fixes a defect
  # - test           # fixes/modifies tests
  # - maintenance    # not directly related to the code
  # - release        # related to a new release preparation
  # - documentation  # change in code docs, haddocks...

Context

Some help texts were misleading, they were mentioning CBOR in JSON arguments and were referencing "special JSON schema" where "detailed JSON schema" should be used.
This is a partial fix for: #593

Checklist

• Commit sequence broadly makes sense and commits have useful messages
• New tests are added if needed and existing tests are updated. See Running tests for more details
• Self-reviewed the diff

[newhoggy]

Very nice!