Finish the integration of webxr into the Cargo workspace (#35229)

- Run `cargo fmt` on `webxr` and `webxr-api`
- Fix clippy warnings in the existing `webxr` code
- Integrate the new crates into the workspace
- Expose `webxr` via the libservo API rather than requiring embedders to
  depend on it explicitly.

Signed-off-by: Martin Robinson <mrobinson@igalia.com>

components/shared/webxr/Cargo.toml

@@ -1,14 +1,12 @@
 [package]
 name = "webxr-api"
-version = "0.0.1"
-authors = ["The Servo Project Developers"]
-edition = "2018"
-
-homepage = "https://github.com/servo/webxr"
-repository = "https://github.com/servo/webxr"
+version.workspace = true
+authors.workspace = true
+license.workspace = true
+edition.workspace = true
+publish.workspace = true
+rust-version.workspace = true
 keywords = ["ar", "headset", "openxr", "vr", "webxr"]
-license = "MPL-2.0"
-
 description = '''A safe Rust API that provides a way to interact with
 virtual reality and augmented reality devices and integration with OpenXR.
 The API is inspired by the WebXR Device API (https://www.w3.org/TR/webxr/)
@@ -21,8 +19,8 @@ path = "lib.rs"
 ipc = ["serde", "ipc-channel", "euclid/serde"]
 
 [dependencies]
-euclid = "0.22"
-ipc-channel = { version = "0.19", optional = true }
-log = "0.4"
-serde = { version = "1.0", optional = true }
-time = { version = "0.1", optional = true }
+euclid = { workspace = true }
+ipc-channel = { workspace = true, optional = true }
+log = { workspace = true }
+serde = { workspace = true, optional = true }
+time_03 = { workspace = true, optional = true }