perf: Remove pointless memory allocation for gridSelectionHasItem

[ImmortalRabbit]

Remove pointless allocation for gridSelectionHasItem according to FIXME

[Copilot]

Pull Request Overview

This PR optimizes the gridSelectionHasItem function by removing an unnecessary array allocation that was creating a temporary array to check selection ranges. Instead of creating an array to combine sel.current.range and sel.current.rangeStack, the code now checks the current range directly and then iterates through the range stack separately.

• Eliminates pointless memory allocation by avoiding array creation and spread operation
• Maintains the same functionality while improving performance
• Addresses a FIXME comment indicating the optimization opportunity

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[Copilot]

[nitpick] This line is quite long and complex with multiple property accesses. Consider extracting variables for sel.current.range and the boundary calculations to improve readability.

Suggested change

	if (col >= sel.current.range.x && col < sel.current.range.x + sel.current.range.width && row >= sel.current.range.y && row < sel.current.range.y + sel.current.range.height) return true;
	const range = sel.current.range;
	const xMin = range.x;
	const xMax = range.x + range.width;
	const yMin = range.y;
	const yMax = range.y + range.height;
	if (col >= xMin && col < xMax && row >= yMin && row < yMax) return true;