This PR addresses an issue with TextPainter's caret position calculation for text containing full-width spaces. Currently, the caret position is not accurately calculated for strings with full-width spaces. To resolve this, the following changes have been made:
Corrected the logic for caret position calculation when full-width spaces are present in the text.
Added and updated test cases to ensure accurate caret position calculation.
These changes ensure that the caret position for text with full-width spaces is computed correctly.
This issue was introduced by the commit [a0a854a](a0a854a78b).
Related Issue: [#149099](https://github.com/flutter/flutter/issues/149099)
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