Auto merge of #24708 - szeged:webgpu-base, r=gterzian,kvark

Initial implementation of WebGPU API

<!-- Please describe your changes on the following line: -->
- Added the WebIDL bindings for GPU and GPUadapter interfaces.
- Created a background thread for WebGPU api calls.
- Established the async communication between the background thread and the WebGPU interfaces.
- Implemented the `requesAdapter` function of `navigator.gpu`

`./mach test-tidy` reports an error due to the different `arrayvec` version used in `servo` and `webgpu`, so added it to the ignore list in `servo-tidy.toml`

---
<!-- Thank you for contributing to Servo! Please replace each `[ ]` by `[X]` when the step is complete, and replace `___` with appropriate data: -->
- [x] `./mach build -d` does not report any errors
- [ ] `./mach test-tidy` does not report any errors
- [ ] These changes addresses a part of #https://github.com/servo/servo/issues/24706

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cc @jdm, cc @kvark

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components/script/script_thread.rs

@@ -163,6 +163,7 @@ use style::dom::OpaqueNode;
 use style::thread_state::{self, ThreadState};
 use time::{at_utc, get_time, precise_time_ns, Timespec};
 use url::Position;
+use webgpu::WebGPU;
 use webrender_api::units::LayoutPixel;
 use webrender_api::{DocumentId, RenderApiSender};
 use webvr_traits::{WebVREvent, WebVRMsg};
@@ -629,6 +630,9 @@ pub struct ScriptThread {
     /// A handle to the WebGL thread
     webgl_chan: Option<WebGLPipeline>,
 
+    /// A handle to the WebGPU threads
+    webgpu: Option<WebGPU>,
+
     /// A handle to the webvr thread, if available
     webvr_chan: Option<IpcSender<WebVRMsg>>,
 
@@ -1338,6 +1342,7 @@ impl ScriptThread {
             layout_to_constellation_chan: state.layout_to_constellation_chan,
 
             webgl_chan: state.webgl_chan,
+            webgpu: state.webgpu,
             webvr_chan: state.webvr_chan,
             webxr_registry: state.webxr_registry,
 
@@ -3247,6 +3252,7 @@ impl ScriptThread {
             incomplete.navigation_start,
             incomplete.navigation_start_precise,
             self.webgl_chan.as_ref().map(|chan| chan.channel()),
+            self.webgpu.clone(),
             self.webvr_chan.clone(),
             self.webxr_registry.clone(),
             self.microtask_queue.clone(),