Update to wgpu 0.17 & latest egui

[Wumpf]

What

• Depends on Improved wgpu callbacks emilk/egui#3253
  • allows for a bit nicer callback handling on our side. Still not amazing but quite a bit better I reckon (no more locks and additional ref counting on our side!). I was hoping to use the new, more flexible shared_paint_callback_resources to store ViewBuilder, but it can't be accessed without a handle to the eframe renderer.
    The end goal would be to get rid of re_renderer's per_frame_data_helper. This will likely be enabled with wgpu's "Arcanization" effort as this will eliminate wgpu::RenderPass's lifetime dependency. In that case we could store a Mutex<ViewBuilder> on ReRendererCallback 🤔
• For the forseeable future we'll have to enable fragile-send-sync-non-atomic-wasm on wgpu (luckily egui itself no longer has this restriction). The problem is that a lot of our infrastructure is built around assuming Send/Sync whereas in actuality webgpu rendering resources can't be shared accross threads easily.
• Had to (discover and) work around [glsl-out] Incorrect rounding for max-float constant expression gfx-rs/wgpu#4568

Checklist

• I have read and agree to Contributor Guide and the Code of Conduct
• I've included a screenshot or gif (if applicable)
• I have tested demo.rerun.io (if applicable)
• Test WebGPU build

• PR Build Summary
• Docs preview
• Examples preview

[abey79]

Very glad to have this! I'm hardly able to comment about the code, but I made a note of my new favourite egui commit :)

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Depends on emilk/egui#3260 now

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Last commit fixes a Chrome only bug that Naga doesn't catch yet, see gfx-rs/naga#2439
With that this version runs fine with WebGPU & Chrome again :)

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(note that this fix was unrelated to the update here; this is rather keeping up with Chrome / the spec)

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ignoring failed pr body update ci