refactor: allow for transparent header

src/core.rs

@@ -39,6 +39,7 @@ pub struct Window {
     pub show_close: bool,
     pub show_maximize: bool,
     pub show_minimize: bool,
+    pub transparent_header: bool,
     pub is_maximized: bool,
     height: f32,
     width: f32,
@@ -169,6 +170,7 @@ impl Default for Core {
                 show_minimize: true,
                 show_window_menu: false,
                 is_maximized: false,
+                transparent_header: false,
                 height: 0.,
                 width: 0.,
             },