fix/caret: Fix caret and formatting issue

[Sidsector9]

Description of the Change

Closes #34
Closes #208

How to test the Change

Please see the respective issues for testing instructions.

Changelog Entry

Fixed - Issue with blocks crashing due to faux caret
Fixed - Issue with characters added to the beginning trimming text from the end

Credits

Props @dkotter @Sidsector9

Checklist:

• I agree to follow this project's Code of Conduct.
• I have updated the documentation accordingly.
• I have added tests to cover my change.
• All new and existing tests pass.

[ankitguptaindia]

@Sidsector9 This PR fixed the issues reported in both connected issues but I am facing issue in a specific scenario when user select whole content which has any special character.

It is showing This block has encountered an error and cannot be previewed.

Issue.mp4

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For QA Use only: RTL Sites:

RTL.mp4

[ankitguptaindia]

QA/Test Report- ✅

Testing Environment -

• WordPress: 6.5-alpha-57029
• PHP: 8.0.30
• Server: nginx/1.16.0
• Database: mysqli (Server: 5.7.28 / Client: 8.0.30)
• Browser: Chrome 118.0.0.0
• OS: macOS
• Theme: Twenty Twenty-Four 1.0

Actual Results

• Both Connected issues have been fixed. ✅
• Issue Reported in QA Feedback has been addressed and fixed. ✅
• Also tested in RTL & LTR sites, issues have been fixed. ✅

ISC.mp4