Merged in feat/SW-2782-create-sas-branded-header (pull request #2878)

feat(SW-2782): Updated header as per design, added language switcher and user menu

* feat(SW-2782): Updated header as per design, added language switcher and user menu

* feat(SW-2782): Updated UI as per design

* feat(SW-2782): Optimised code with use of Popover and modal from RAC


Approved-by: Anton Gunnarsson

yarn.lock

@@ -6054,10 +6054,12 @@ __metadata:
     next: "npm:15.3.4"
     next-auth: "npm:5.0.0-beta.29"
     react: "npm:^19.0.0"
+    react-aria-components: "npm:^1.8.0"
     react-dom: "npm:^19.0.0"
     react-intl: "npm:^7.1.11"
     server-only: "npm:^0.0.1"
     typescript: "npm:5.8.3"
+    usehooks-ts: "npm:3.1.1"
     vitest: "npm:^3.2.4"
   languageName: unknown
   linkType: soft