initial macos porting work

lib/ui/src/runtime.rs

@@ -110,6 +110,7 @@ impl WindowController {
     }
 
     /// Copies plain text to the platform primary-selection buffer for this window.
+    #[cfg(target_os = "linux")]
     pub fn set_primary_selection_text(
         &self,
         text: impl Into<String>,
@@ -128,6 +129,7 @@ impl WindowController {
     }
 
     /// Requests the current plain-text primary selection contents from the platform.
+    #[cfg(target_os = "linux")]
     pub fn request_primary_selection_text(&self) -> Result<(), PlatformClosed> {
         self.proxy.request_primary_selection_text(self.id)
     }