[lexical-offset] Bug Fix: inline element selection, match user input observed behaviour with text nodes

[felzsoca]

Description

inline element selection (multiple)
prefer text node end over next node start (TODO should detail out separately for collapsed selection?)

Describe the changes in this pull request

Closes #7580 (TODO double-check and create bugs for the other issues...)

Test plan

Before

Insert relevant screenshots/recordings/automated-tests

After

Insert relevant screenshots/recordings/automated-tests

[vercel]

The latest updates on your projects. Learn more about Vercel for GitHub.

Project	Deployment	Preview	Comments	Updated (UTC)
lexical	Ready	Preview	Comment	Aug 19, 2025 4:37pm
lexical-playground	Ready	Preview	Comment	Aug 19, 2025 4:37pm

[etrepum]

The most important thing to do when adding fixes here would be to add tests that show what the fixes are supposed to do, confirm that they work, and ensure that they continue to work as the rest of the code changes.

[felzsoca]

Hi @etrepum,

thanks for checking the PR! You are right, the PR is not there yet, hence I created just as a draft one.
I started to add unit tests locally, but as there was none before for this package, it takes a little longer. I also add some nice helpers via which it is easier to arrange the tests.
I plan to have multiple commits with different test cases, just would like to have an 'acceptable' first one as I already had an idea for arranging nodes. Will get back to it tomorrow.