optimized line rendering and updated render_lines API

sandbox/basic.py

@@ -174,3 +174,6 @@ if __name__ == "__main__":
     from textual.css.scalar import Scalar
 
     print(Scalar.resolve_dimension.cache_info())
+
+    from rich.style import Style
+    print(Style.__add__.cache_info())

sandbox/table.py

@@ -21,10 +21,14 @@ class TableApp(App):
 
     def on_mount(self):
         self.bind("d", "toggle_dark")
+        self.bind("z", "toggle_zebra")
 
     def action_toggle_dark(self) -> None:
         self.app.dark = not self.app.dark
 
+    def action_toggle_zebra(self) -> None:
+        self.table.zebra_stripes = not self.table.zebra_stripes
+
 
 app = TableApp()
 if __name__ == "__main__":