use local-channel instead of tokio sync channel (#179)

this avoids the mutex overhead in tokio

Cargo.lock

@@ -1324,6 +1324,7 @@ dependencies = [
  "lan-mouse-proto",
  "libadwaita",
  "libc",
+ "local-channel",
  "log",
  "serde",
  "serde_json",
@@ -1403,6 +1404,23 @@ version = "0.4.14"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "78b3ae25bc7c8c38cec158d1f2757ee79e9b3740fbc7ccf0e59e4b08d793fa89"
 
+[[package]]
+name = "local-channel"
+version = "0.1.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b6cbc85e69b8df4b8bb8b89ec634e7189099cea8927a276b7384ce5488e53ec8"
+dependencies = [
+ "futures-core",
+ "futures-sink",
+ "local-waker",
+]
+
+[[package]]
+name = "local-waker"
+version = "0.1.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "4d873d7c67ce09b42110d801813efbc9364414e356be9935700d368351657487"
+
 [[package]]
 name = "lock_api"
 version = "0.4.12"