Rename livekit_server to livekit_api (#24984)

The name `livekit_server` was a bit misleading as it is not a server and
gets built into both the client and server - the server code is in
`collab`.

Release Notes:

- N/A

crates/livekit_client_macos/examples/test_app_macos.rs

@@ -2,8 +2,8 @@ use std::time::Duration;
 
 use futures::StreamExt;
 use gpui::{actions, KeyBinding, Menu, MenuItem};
+use livekit_api::token::{self, VideoGrant};
 use livekit_client_macos::{LocalAudioTrack, LocalVideoTrack, Room, RoomUpdate};
-use livekit_server::token::{self, VideoGrant};
 use log::LevelFilter;
 use simplelog::SimpleLogger;