fix(editor): preserve indentation on soft-wrapped lines

[bajrangCoder]

Fixes: #2504

[greptile-apps]

Confidence Score: 5/5

The PR appears safe to merge, with no outstanding findings.

Summary

• Introduces a view plugin that measures available width and decorates visible indented lines.
• Replaces standard line wrapping with the new extension when text wrapping is enabled.
• Adds unit coverage for spaces, tabs, mixed indentation, tab alignment, and indentation caps.

_{Reviews (3) · Last reviewed commit: "fix"}