Add base authenticated route

matrixgw_frontend/src/widgets/dashboard/mixins.ts

@@ -0,0 +1,23 @@
+import { type Theme } from "@mui/material/styles";
+
+export function getDrawerSxTransitionMixin(
+  isExpanded: boolean,
+  property: string
+) {
+  return {
+    transition: (theme: Theme) =>
+      theme.transitions.create(property, {
+        easing: theme.transitions.easing.sharp,
+        duration: isExpanded
+          ? theme.transitions.duration.enteringScreen
+          : theme.transitions.duration.leavingScreen,
+      }),
+  };
+}
+
+export function getDrawerWidthTransitionMixin(isExpanded: boolean) {
+  return {
+    ...getDrawerSxTransitionMixin(isExpanded, "width"),
+    overflowX: "hidden",
+  };
+}