QQuickImageParticle may crash during sprite engine reinitialization

I'm seeing crashes in QQuickImageParticle when the window is moving between screens with different devicePixelRatio's. Here's a sample stack trace:

Qt6Quickd.dll!QQuickSpriteEngine::spriteWidth(int sprite) Line 255	C++
Qt6QuickParticlesd.dll!QQuickImageParticle::initialize(int gIdx, int pIdx) Line 1780	C++
Qt6QuickParticlesd.dll!QQuickParticlePainter::load(QQuickParticleData * d) Line 115	C++
Qt6QuickParticlesd.dll!QQuickParticleSystem::finishNewDatum(QQuickParticleData * pd) Line 945	C++
Qt6QuickParticlesd.dll!QQuickParticleSystem::emitParticle(QQuickParticleData * pd, QQuickParticleEmitter * particleEmitter) Line 932	C++
Qt6QuickParticlesd.dll!QQuickParticleEmitter::emitWindow(int timeStamp) Line 452	C++
Qt6QuickParticlesd.dll!QQuickParticleSystem::updateCurrentTime(int currentTime) Line 973	C++
Qt6QuickParticlesd.dll!QQuickParticleSystemAnimation::updateCurrentTime(int t) Line 448	C++

QQuickImageParticle will call createEngine at runtime in response to various events, including DPR changes. From what I can tell, this process is not instantaneous, and if particle emission happens in the right moment, the m_sprites array will be empty, and the rest of the code doesn't seem to handle that case.

Below is a reasonably minimal repro case. The bug can be triggered by either moving the window to a different-dpr screen (at least on Windows), or by clicking the window a few times. The MouseArea's onClicked handler triggers a change to the `sprites` list, which in turn triggers createEngine.

import QtQuick
import QtQuick.Particles

Window {
	width: 500
	height: 500
	visible: true
	ParticleSystem {
		anchors.fill: parent

		Sprite{ id: s1; source:"image.png"}
		Sprite{ id: s2; source:"image.png"}
		ImageParticle{
			id: ipa
			sprites: [ s1 ]
		}

		MouseArea {
			anchors.fill: parent
			onClicked: {
				if(ipa.sprites.length == 1)
					ipa.sprites.push(s2)
				else
					ipa.sprites.length = 1
			}
		}

		Emitter {
			id: emitter
			lifeSpan: 1500
			velocity: AngleDirection {
				angleVariation: 360
				magnitude: 15
			}
			emitRate: 30
			anchors.centerIn: parent
		}
	}
}