Use LiveKit's Rust SDK on Linux while continue using Swift SDK on Mac (#21550)

Similar to #20826 but keeps the Swift implementation. There were quite a
few changes in the `call` crate, and so that code now has two variants.

Closes #13714

Release Notes:

- Added preliminary Linux support for voice chat and viewing
screenshares.

---------

Co-authored-by: Kirill Bulatov <mail4score@gmail.com>
Co-authored-by: Kirill Bulatov <kirill@zed.dev>
Co-authored-by: Mikayla <mikayla@zed.dev>

crates/gpui/src/geometry.rs

@@ -704,6 +704,11 @@ pub struct Bounds<T: Clone + Default + Debug> {
     pub size: Size<T>,
 }
 
+/// Create a bounds with the given origin and size
+pub fn bounds<T: Clone + Default + Debug>(origin: Point<T>, size: Size<T>) -> Bounds<T> {
+    Bounds { origin, size }
+}
+
 impl Bounds<Pixels> {
     /// Generate a centered bounds for the given display or primary display if none is provided
     pub fn centered(display_id: Option<DisplayId>, size: Size<Pixels>, cx: &AppContext) -> Self {