macos: hook up clipboards

src/App.zig

@@ -368,6 +368,11 @@ pub const CAPI = struct {
         };
     }
 
+    /// Return the userdata associated with the app.
+    export fn ghostty_app_userdata(v: *App) ?*anyopaque {
+        return v.runtime.opts.userdata;
+    }
+
     export fn ghostty_app_free(ptr: ?*App) void {
         if (ptr) |v| {
             v.destroy();
@@ -400,6 +405,11 @@ pub const CAPI = struct {
         if (ptr) |v| v.app.closeWindow(v);
     }
 
+    /// Returns the app associated with a surface.
+    export fn ghostty_surface_app(win: *Window) *App {
+        return win.app;
+    }
+
     /// Tell the surface that it needs to schedule a render
     export fn ghostty_surface_refresh(win: *Window) void {
         win.window.refresh();