* move setLang() to a root layout

* fix: findLang only returns acceptable languages
* fix: fallback to use header x-lang if we haven't setLang yet
* fix: languageSchema, allow uppercase

Approved-by: Linus Flood

app/[lang]/webview/layout.tsx

@@ -10,7 +10,6 @@ import GTMScript from "@/components/TrackingSDK/GTMScript"
 import RouterTracking from "@/components/TrackingSDK/RouterTracking"
 import { getIntl } from "@/i18n"
 import ServerIntlProvider from "@/i18n/Provider"
-import { setLang } from "@/i18n/serverContext"
 
 import styles from "./layout.module.css"
 
@@ -26,7 +25,6 @@ export default async function RootLayout({
   children,
   params,
 }: React.PropsWithChildren<LayoutArgs<LangParams>>) {
-  setLang(params.lang)
   const { defaultLocale, locale, messages } = await getIntl()
 
   return (