SPZ v4 crashes in SPZLoader

[bhouston]

Description

Reported here: #33950 (comment) by @hybridherbst. Just making a formal issue to track a fix:

Is it expected that the current version of SPZ (SPZ 4) doesn't work?

It throws an error:

fflate.module.js:987 Uncaught (in promise) Error: invalid gzip data
    at gzs (fflate.module.js:987:9)
    at gunzipSync (fflate.module.js:1377:14)
    at SPZLoader.parse (SPZLoader.js:98:24)
    at Object.onLoad (SPZLoader.js:68:19)
    at FileLoader.js:283:38

This is exported from https://superspl.at/editor.
The file in SPZ4 format: https://drive.google.com/file/d/1iKXfHUrxy-xGhiIZNND4LogRtBw6F7GN/view?usp=sharing

Reproduction steps

1. Load the example SPZ4 file using the SPZLoader.
2. It will crash.

Code

const splatData = await new SPZLoader().loadAsync('lion.spz');
const splats = new GaussianSplatMesh(splatData);

scene.add(splats);

Live example

n/a

Screenshots

No response

Version

dev branch

Device

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Browser

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OS

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