Revert "Use livekit's Rust SDK instead of their swift SDK (#13343)" (#20809)

Issues found:

* audio does not work well with various set-ups using USB
* switching audio during initial join may leave the client with no audio
at all
* audio streaming is done on the main thread, beachballing certain
set-ups
* worse screenshare quality (seems that there's no dynamic scaling
anymore, compared to the Swift SDK)

This reverts commit 1235d0808e.

Release Notes:

- N/A

crates/media/Cargo.toml

@@ -17,7 +17,6 @@ anyhow.workspace = true
 
 [target.'cfg(target_os = "macos")'.dependencies]
 core-foundation.workspace = true
-ctor.workspace = true
 foreign-types = "0.5"
 metal = "0.29"
 objc = "0.2"

crates/media/src/media.rs

@@ -253,14 +253,11 @@ pub mod core_media {
             }
         }
 
-        pub fn image_buffer(&self) -> Option<CVImageBuffer> {
+        pub fn image_buffer(&self) -> CVImageBuffer {
             unsafe {
-                let ptr = CMSampleBufferGetImageBuffer(self.as_concrete_TypeRef());
-                if ptr.is_null() {
-                    None
-                } else {
-                    Some(CVImageBuffer::wrap_under_get_rule(ptr))
-                }
+                CVImageBuffer::wrap_under_get_rule(CMSampleBufferGetImageBuffer(
+                    self.as_concrete_TypeRef(),
+                ))
             }
         }