Bug: swapChildren doesn't change rendering order unless the zIndex updated for all children

[bpstudio]

Current Behavior

swapChildren doesn't change rendering order unless the zIndex updated for all children

Expected Behavior

The rendering order should change when swapChildren used

Steps to Reproduce

https://www.pixiplayground.com/#/edit/Gwo_yVLnp9LxWZzEQS3Z-

after swapping two children, the rendering order doesn't change

app.stage.swapChildren(app.stage.getChildAt(i), app.stage.getChildAt(i+1))

when add values to zIndex, the order changes properly

for(let c=0; c < app.stage.children.length; c++) {
                    app.stage.getChildAt(c).zIndex = c;
} 

Environment

• pixi.js version: 8.1.1
• Browser & Version: *Chrome 125.0.6422.142 *
• OS & Version: MacOS Sonoma 14.4.1
• Running Example: https://www.pixiplayground.com/#/edit/Gwo_yVLnp9LxWZzEQS3Z-)

Possible Solution

Reindexing all children

Additional Information

My example is not perfect, however, it shows the issue.