Make StoreOp an enum instead of a bool

[Wumpf]

Checklist

• Run cargo clippy.
• Run cargo clippy --target wasm32-unknown-unknown if applicable.
• Add change to CHANGELOG.md. See simple instructions inside file.

Connections

• fixes Depth target gets cleared before compute pass when previously used as attachement without storing values #4146
  • (description is actually not indicative of the actual error but of the common misconception this avoids)

Description

wgpu::Operations::store used to be an underdocumented boolean value,
causing missunderstandings of the effect of setting it to false.

The API now resembles WebGPU which distinguishes store and discard,
see WebGPU spec on GPUStoreOp.

// ...
depth_ops: Some(wgpu::Operations {
    load: wgpu::LoadOp::Clear(1.0),
-   store: false,
+   store: wgpu::StoreOp::Discard,
}),
// ...

Opted to put this text into the changelog under Major Changes since it breaks like every single use ;-)

[cwfitzgerald]

Comments, like the api change!

[Wumpf]

Thanks for all the comment improvements and keeping the bar for documentation high!

[cwfitzgerald]

Did you miss a push, a couple resolved things are still unaddressed

[Wumpf]

Did you miss a push

eh, yeah I managed to push to the wrong remote 🤦

[teoxoy]

LGTM!