🧪 [tests] Add Polygon2D tests for Intersects and core methods

[johnstrand]

🎯 What: Missing test coverage for Polygon2D methods including Intersects(Polygon2D), Intersects(Polygon2D, out Vector2?), Intersects(Line), Intersects(Line, out Vector2?), constructor validations, Contains, and TranslateBy.

📊 Coverage: Added test cases covering:

• Constructor vertex array empty validation and clockwise vertex sorting.
• Polygon point containment (Contains).
• Polygon translation and bounding box updating (TranslateBy).
• Intersection check between polygons with disjoint bounding boxes, overlapping edges, and overlapping bounding boxes without edge intersections.
• Polygon-Line intersection checks with and without returning intersection points.

✨ Result: Improved test coverage and reliability for Polygon2D.

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PR created automatically by Jules for task 11613147297087028936 started by @johnstrand

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