Code Quality: Prevent exceptions when available size is zero or negative

[seer-by-sentry]

Resolved / Related Issues

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• Closes FILES-APP-3H6

Steps used to test these changes

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1. The issue was that: BreadcrumbBar's ItemsRepeater received zero width from parent Grid, causing WinUI's MeasureOverride to divide by zero.
2. Prevents DivideByZeroException in WinUI when availableSize has zero dimensions by providing a minimal positive size for measurement.
3. Handles zero or negative available width by hiding all items in the breadcrumb bar.

This fix was generated by Seer in Sentry, triggered by Yair. 👁️ Run ID: 903159

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[Copilot]

Pull Request Overview

This PR fixes a DivideByZeroException in the BreadcrumbBar control that occurred when the available size was zero or negative. The fix ensures proper measurement and visibility handling when the breadcrumb bar receives insufficient space.

• Prevents division by zero exceptions in WinUI by providing minimum positive size for measurements
• Hides all breadcrumb items when available width is zero or negative
• Maintains the original layout logic while adding safety checks for edge cases

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[MohammadSamiIslam]

This should return early if the children count is zero or no children available
if (context?.Children == null || context.Children.Count == 0)
{
return Size.Empty;
}

[yaira2]

Are you able to follow up with a PR? We're currently working on polishing things up for v4, but this should be a quick one to review.

[MohammadSamiIslam]

yeah, sure. was there an issue number for this?

[yaira2]

Not currently

[MohammadSamiIslam]

@yaira2 I have created a PR: #17483
Let me know if that helps