Fix GDI+ crash in FillRectangle with AntiAlias and 24bppRgb

[Copilot]

Fixes #14113

Proposed changes

• Added coordinate clipping in FillRectangle, FillRectangles, and DrawImage overloads to prevent GDI+ out-of-bounds writes when using SmoothingMode.AntiAlias with PixelFormat.Format24bppRgb
• When drawing outside bitmap bounds with this specific combination, coordinates are now clipped to valid ranges before calling GDI+
• Rectangles completely outside bounds are skipped; partially out-of-bounds rectangles are clipped to the intersection

Customer Impact

• Prevents ExecutionEngineException (fatal process crash in .NET 9+) and AccessViolationException (.NET 8) when drawing with antialiasing on 24bpp RGB bitmaps
• Applications using this specific combination will now continue running instead of crashing

Regression?

• No

Risk

• Low. Change only affects the specific problematic combination (AntiAlias + Format24bppRgb + out-of-bounds drawing). Other scenarios pass through unchanged.

Test methodology

• Added comprehensive test coverage for various out-of-bounds scenarios with the problematic combination
• Verified in-bounds drawing still works correctly
• Verified other SmoothingMode and PixelFormat combinations are unaffected
• Tested with reproduction case from issue Crash (AccessViolationException/ExecutionEngineException) graphics.FillRectangle into Bitmap with Format24bppRgb #14113

Test environment(s)

• .NET 9.0
• Windows 11

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