Fix cursor editor icon width calculation for proper DPI scaling

[Copilot]

Fixes #14167

Root Cause

Icons similar to HSplit.cur, VSplit.cur are wider than other icons at certain DPI settings (such as 125%, 175%， 225%， 250%), which is causing the webtable to display abnormally.

Proposed changes

• Modify the drawing method for list items to use the default icon width as a reference, ensuring that all icons are the same size.

Customer Impact

• Cursor editor items are displayed correctly in propertyGrid with all DPI settings.

Regression?

• No

Risk

• Minimal

Screenshots

Before

After

150DPI:

150DPI.mp4

175DPI:

175DPI.mp4

200DPI:

200DPI.mp4

225DPI:

225DPI.mp4

Test methodology

• Manually

Test environment(s)

• 11.0.0-alpha.1.25619.109

Microsoft Reviewers: Open in CodeFlow

[codecov]

Codecov Report

❌ Patch coverage is 20.00000% with 4 lines in your changes missing coverage. Please review.
✅ Project coverage is 77.15598%. Comparing base (05b7c2e) to head (82db747).

Additional details and impacted files

@@                 Coverage Diff                 @@
##                main      #14168         +/-   ##
===================================================
- Coverage   77.15877%   77.15598%   -0.00280%     
===================================================
  Files           3279        3279                 
  Lines         645333      645333                 
  Branches       47720       47720                 
===================================================
- Hits          497931      497913         -18     
- Misses        143719      143724          +5     
- Partials        3683        3696         +13     

Flag	Coverage Δ
Debug	77.15598% <20.00000%> (-0.00280%)	⬇️
integration	18.98842% <0.00000%> (-0.01568%)	⬇️
production	52.02345% <20.00000%> (-0.00626%)	⬇️
test	97.40559% <ø> (ø)
unit	49.47022% <20.00000%> (+0.02777%)	⬆️

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[SimonZhao888]

Here is another issue: when the DPI is set to 125%, 175%, 225%, 250%, the .cur icon exhibits an icon offset problem.
Normal：

Offset：