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

typos.toml

@@ -22,7 +22,7 @@ extend-exclude = [
     # Stripe IDs are flagged as typos.
     "crates/collab/src/db/tests/processed_stripe_event_tests.rs",
     # Not our typos.
-    "crates/livekit_server/",
+    "crates/livekit_api/",
     # Vim makes heavy use of partial typing tables.
     "crates/vim/",
     # Editor and file finder rely on partial typing and custom in-string syntax.