[bug] Sometimes the inner corner doesn't align with the next outer corner

**Describe the bug**
Sometimes the inner corner doesn't align with the next outer corner

**To Reproduce**
Use a textfield with two lines, one sighly smaller or bigger than the other

**Expected behavior**
A clear and concise description of what you expected to happen.

**Screenshots**

**Additional context**
N/A

Start by reproducing the issue with a Flutter TextField containing two lines of slightly different lengths, using the screenshot as the visual reference. Trace the text highlighting and corner rendering entry points, then confirm that the inner corner aligns with the next outer corner for both larger and smaller lines.

Written by the indexing model from the issue text.