feat: video publishing (#42)

- Prepare webrtc abstraction ( for future wasm support )
- Added track publish support for videos
  - Added LogoTrack example to simple_room demo
- Lot of cleanup
- There are compiler warnings I'll solve on our v1 release

webrtc-sys/include/livekit/webrtc.h

@@ -18,6 +18,7 @@
 
 #include "rtc_base/physical_socket_server.h"
 #include "rtc_base/ssl_adapter.h"
+#include "rust/cxx.h"
 
 #ifdef WEBRTC_WIN
 #include "rtc_base/win32_socket_init.h"
@@ -54,6 +55,8 @@ class RTCRuntime {
 #endif
 };
 
+rust::String create_random_uuid();
+
 std::shared_ptr<RTCRuntime> create_rtc_runtime();
 
 }  // namespace livekit