Fix shaderParticle assignment (#7787)

[michaelfranzl]

Fixes #7787

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[mvaligursky]

Well spotted, thanks!

[Copilot]

Pull Request Overview

This PR corrects the property used for the “stop” update shader in ParticleEmitter by renaming it to better reflect its purpose.

• Rename shaderParticleUpdateNoRespawn to shaderParticleUpdateOnStop to match the ON_STOP define.

Comments suppressed due to low confidence (1)

src/scene/particle-system/particle-emitter.js:695

• After renaming this property, update all references to shaderParticleUpdateNoRespawn elsewhere in the class or consuming code to shaderParticleUpdateOnStop to prevent undefined property errors at runtime.

        this.shaderParticleUpdateOnStop = ShaderUtils.createShader(gd, shaderOptions);