Users with view-only permissions cannot comment on selected text

[lbittner-pdftron]

Describe the bug

When a user with view-only permissions highlights some text and creates a comment, the comment is applied to the entire document and not just the selected text.

To Reproduce

1. Log in as a user with view-only permissions
2. Navigate to a document with a portable text field
3. Highlight some of the text and click "Add comment"
4. Write and submit the comment

Note that the comment is created, but not applied to the selected text.

Logging in as a user with full permissions resolves this issue.

Expected behaviour

A read-only user should be able to comment on the selected content

Which versions of Sanity are you using?

@sanity/cli (global)               4.10.1 (latest: 4.11.0)
@sanity/asset-utils                 1.3.0 (latest: 2.3.0)
@sanity/block-content-to-markdown   1.0.0 (up to date)
@sanity/code-input                  4.1.4 (latest: 6.0.3)
@sanity/image-url                   1.0.2 (latest: 1.2.0)
@sanity/orderable-document-list     1.2.2 (latest: 1.4.0)
@sanity/portable-text-editor       3.48.1 (up to date)
@sanity/table                       1.1.2 (latest: 2.0.0)
@sanity/types                      3.16.2 (latest: 4.11.0)
@sanity/vision                     3.79.0 (latest: 4.11.0)
@sanity/webhook                     3.0.1 (latest: 4.0.4)
sanity                             4.10.1 (latest: 4.11.0)

What operating system are you using?

MacOS, can be produced in Windows as well

Which versions of Node.js / npm are you running?

Node v20.19.4