fix: isolate macos-specific dependencies (#6854)

Release Notes:
- N/A

crates/fsevent/examples/events.rs

@@ -1,10 +1,12 @@
-use fsevent::EventStream;
-use std::{env::args, path::Path, time::Duration};
-
+#[cfg(target_os = "macos")]
 fn main() {
+    use fsevent::EventStream;
+    use std::{env::args, path::Path, time::Duration};
+
     let paths = args().skip(1).collect::<Vec<_>>();
     let paths = paths.iter().map(Path::new).collect::<Vec<_>>();
     assert!(!paths.is_empty(), "Must pass 1 or more paths as arguments");
+
     let (stream, _handle) = EventStream::new(&paths, Duration::from_millis(100));
     stream.run(|events| {
         eprintln!("event batch");
@@ -14,3 +16,8 @@ fn main() {
         true
     });
 }
+
+#[cfg(not(target_os = "macos"))]
+fn main() {
+    eprintln!("This example only works on macOS");
+}