Adds FillExtents as a fourth nesting phase in both FindBestFill and
Fill(groupParts, Box), running at bestRotation and bestRotation+90°.
Updates Description to reflect the new phase.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
The Size fix (d4222db) changed Size.Width to Y axis and Size.Length to
X axis but only updated DrawPlate/LayoutViewGL. BoundingBox, WorkArea,
rotations, DXF export, and engine code still used the old Width=X
convention, causing the fill engine to get a swapped work area (60x120
instead of 120x60) and parts to fill in the wrong direction.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
