fix: correct coordinate system for click and drag selections

[MinCrohn]

This resolves a bug where click and drag-select events would detect intersections at incorrect locations when the viewport was zoomed or panned.

The root cause was a coordinate system mismatch within the intersection logic. Mouse event coordinates in world space were being incorrectly compared with object coordinates in local space.

This patch corrects the issue by ensuring all intersection calculations and visual feedback drawings are performed in a consistent coordinate system

[gemini-code-assist]

Summary of Changes

Hello @MinCrohn, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request resolves a critical bug affecting click and drag-select functionality, where object intersections were miscalculated due to inconsistent coordinate systems, particularly when the viewport was transformed. My changes standardize how mouse events and object boundaries are converted to a consistent coordinate space, ensuring accurate selection behavior. I've also added comprehensive tests to validate the fix across various viewport states.

Highlights

• Coordinate System Alignment: I've addressed a bug where click and drag-select events would incorrectly detect intersections, especially when the viewport was zoomed or panned. The core fix involves standardizing coordinate system transformations across all intersection calculations and visual feedback drawings.
• Refactored Event Handling: The drag-select.js and single-select.js event handlers now directly convert global mouse event coordinates to world coordinates using viewport.toWorld(e.global), eliminating reliance on a separate getPointerPosition utility. This ensures consistency and accuracy.
• Improved Intersection Logic: The underlying intersection detection (intersect-point.js and intersect.js) has been updated to use a new getObjectLocalCorners utility. This function accurately transforms display object corners into the viewport's local coordinate system, providing correct input for polygon intersection checks.
• New Utility Functions: I've introduced getViewport to reliably retrieve the associated viewport for any display object by traversing its parent chain, and getObjectLocalCorners to provide object boundary points in the viewport's local space. The old get-points.js utility has been removed as its functionality is now superseded.
• Comprehensive Test Coverage: Extensive new tests have been added to patchmap.test.js specifically for the select functionality. These tests validate the accuracy of object selection under various viewport conditions, including different zoom levels and panning, ensuring the coordinate system fix is robust.

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[gemini-code-assist]

Code Review

This pull request fixes a bug where click and drag-select events would detect intersections at incorrect locations when the viewport was zoomed or panned. The changes ensure all intersection calculations are performed in a consistent coordinate system.

[MinCrohn]

/gemini review

[gemini-code-assist]

Code Review

The pull request addresses a bug related to coordinate system mismatches during click and drag selections. The changes include modifications to event handling, intersection detection, and utility functions to ensure consistent coordinate transformations. The introduction of the selectUnit option enhances the flexibility of object selection.